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#67768 From: Charles Guevara <icecilliate123@...>
Date: Thu Apr 12, 2012 4:07 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
   For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara



________________________________
From: Ricardo Tsukamoto <rictsuk@...>
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Sent: Wednesday, April 11, 2012 11:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Seth,

Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.

Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).

For more than two decades I´ve been using PP vessels for biological cultures
and especially whenever autoclaving will be done. Even my 96-well plates used
for ELISA or for microbiological analysis (coliform, etc.) are of PP and
withstand a long time in use.

Soda-lime glass was said to be a risk for aquatic cultures because - when new -
because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.  

Regards,
Ricardo


________________________________
From: Seth Malovany <enigmaseth@...>
To: Microscope@yahoogroups.com
Sent: Wednesday, April 11, 2012 8:27 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 
Tom:
Depends on the organism. There is a microbe, sometimes many that EAT just about
anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
With Respect
Seth Malovany MT AMT

--- On Wed, 4/11/12, Tom Watson <error253@...> wrote:

From: Tom Watson <error253@...>
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Date: Wednesday, April 11, 2012, 6:46 PM

Wow!

Tom's bubble is doth burst!

Well, truth is truth.

I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!

Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.

Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?

Sent from my iPad

On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:

> Sorry to pop the bubble. They are clear tempered soda-lime glass
> instead of borosilicate. Read the information on the plastic top. In
> my opinion, this is is just one example how industry does a nice job
> deceiving us.
>
> http://en.wikipedia.org/wiki/Pyrex
>
> Especially check the last two paragraphs under COMPOSITION.
>
> Fred
>
> >
> > Also, for those who want cheap petri dishes... Instead of the $$$
> > corning ones or something else, you might try Pyrex kitchen glass. I
> > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > plastic top. Super great deal and they make great petri dishes lol
>
>
>
>
> TODAY(Beta) • Powered by Yahoo!
> Woman goes under the knife for royal look
> Privacy Policy
>
> 

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#67769 From: Tom Watson <error253@...>
Date: Thu Apr 12, 2012 4:46 pm
Subject: Re: Re: Methylene Blue and UV
error253
Send Email Send Email
 
I wanted to take a moment and thank everyone who replied to this thread. I had
not had time at work because I had code which needed quick writing... But
thanks!!!



Sent from my iPad

On Apr 12, 2012, at 8:16 AM, "john896571" <johndean909@...> wrote:

>
>
> Normal saline is 9 grams of NaCl per litre of solution. NaOH is caustic soda!
If you use NaOH, the pH will be around 11-12.
>
> --- In Microscope@yahoogroups.com, "rich_guy_looker" <rich_guy_looker@...>
wrote:
>
> >
> > I'd play around with the Ph
> > of the solution your specimen
> > is in to slightly adjust the spectra
> > (normal saline, 9 grams of NaOH (salt)
> > per liter of water, would be a Ph of 5 to 5.5,
> > with distilled water around Ph 7,
> > but will go lower if sitting in air).
> >
>
>
>
>
> TODAY(Beta) • Powered by Yahoo!
> MLB team bans 'Batman' fan for life
> Privacy Policy
>
>

[Non-text portions of this message have been removed]

#67770 From: Tom Watson <error253@...>
Date: Thu Apr 12, 2012 4:48 pm
Subject: Re: Re: Methylene Blue and UV
error253
Send Email Send Email
 
It sounds like I can expose the chemical to long wave UV and get a nice result.

I wonder if it can be used as a scintillation media. I will test this with
alpha, beta, and gamma this weekend.


Sent from my iPad

On Apr 12, 2012, at 12:08 AM, "rich_guy_looker" <rich_guy_looker@...>
wrote:

> The links below will give you a good idea,
> as in absorption below 400nm
> and emission around 640nm.
>
> I'd play around with the Ph
> of the solution your specimen
> is in to slightly adjust the spectra
> (normal saline, 9 grams of NaOH (salt)
> per liter of water, would be a Ph of 5 to 5.5,
> with distilled water around Ph 7,
> but will go lower if sitting in air).
>
> http://www.stainsfile.info/StainsFile/dyes/52015.htm
>
> Basic info-solubility
>
> http://www.jim.or.jp/journal/e/pdf3/45/12/3334.pdf
>
> Go to "Fig. 4,"
> On the page in the upper-left, labeled "3336"
>
>
http://iopscience.iop.org/1742-6596/182/1/012078/pdf/1742-6596_182_1_012078.pdf
>
> Go to section "3.1. UV–VIS spectra,"
> On the page at the bottom, labeled "2" - Page Number
>
> http://omlc.ogi.edu/spectra/mb/index.html
>
> http://en.wikipedia.org/wiki/File:Methylene_blue_absorption_spectrum.png
>
> http://micro.magnet.fsu.edu/primer/photomicrography/bwstainchart.html
>
> http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000100006
>
> Rich
>
>

[Non-text portions of this message have been removed]

#67771 From: Mark Burgess <fwalgae@...>
Date: Fri Apr 13, 2012 1:24 pm
Subject: Re: Re: Organizing Images
edlnhsnews
Send Email Send Email
 
Picasa can handle RAW files now.

cheers

On 12 April 2012 14:48, Jaava53 <jaava53@...> wrote:
> I think picasa handles well all the basic picture file formats (bmp, jpg, tiff
- this is best to verify from picasa specs) but it cannot handle raw-files
downloaded from camera. At least couldnt few years ago.
>
> I think Picasa is worth to give a shot.
>
> Jaava
>
>
> --- In Microscope@yahoogroups.com, "J. Forster" <jfor@...> wrote:
>>
>> My files are mostly 100K class .jpgs, but there are also some .bmps
>>
>> -John
>>
>> ================
>>
>>
>> > Scanned in images can be saved to TIFF but imported images are all saved
>> > to jpg as you say. Â
>> >
>> >
>> > ________________________________
>> >  From: Jaava53 <jaava53@...>
>> > To: Microscope@yahoogroups.com
>> > Sent: Wednesday, April 11, 2012 11:12 AM
>> > Subject: [Microscope] Re: Organizing Images
>> >
>> >
>> > Â
>> > I like Picasa too, if jpg pixel size is enough for you.
>> > It saves the pics only once, and then you can create albums wich uses your
>> > pics. You can olso make quieries to your pics using date, camera etc. info
>> > in the EXIF data of the pictures.
>> > You do not need to have a net connection when using Picasa, but it has
>> > means to save your pics into net as well.
>> > My wife likes Picasa too, but I have to use a program having a bit more
>> > bit depth for pixels and post processing abilities (Lightroom - not
>> > freeware).
>> >
>> > --- In Microscope@yahoogroups.com, Roger Moretz <stamptrain@> wrote:
>> >>
>> >> As was mentioned earlier, Picasa 3 is a good database but you have to
>> >> organize everything yourself.  Adobe Photoshop Elements is also good
>> >> and costs about $100.  I have played w/both, don't have a preference.
>> >> RogerÂÂ
>> >>
>> >>
>> >> ________________________________
>> >>  From: Microscopeman <microscopeman@>
>> >> To: Microscope@yahoogroups.com
>> >> Sent: Tuesday, April 10, 2012 4:22 PM
>> >> Subject: Re: [Microscope] Organizing Images
>> >>
>> >>
>> >> ÂÂ
>> >> John,
>> >>
>> >> PAXit!, without any measurement or analysis modules (which are options),
>> >> is
>> >> often deployed for "database only" requirements.
>> >>
>> >> It clearly is not freeware.  I'm not aware of any freeware image
>> >> database
>> >> solutions, sorry.
>> >>
>> >> Good luck,
>> >>
>> >> Gregg
>> >>
>> >> ----- Original Message -----
>> >> From: "J. Forster" <jfor@>
>> >> To: <Microscope@yahoogroups.com>
>> >> Sent: Tuesday, April 10, 2012 12:36 PM
>> >> Subject: Re: [Microscope] Organizing Images
>> >>
>> >> > Thanks, but I have no need to analyze the images. I want something,
>> >> very
>> >> > preferably freeware, resident on my PC essentially, to catalog images
>> >> of
>> >> > stuff, sorted in various ways. I am absolutely not interested in
>> >> anything
>> >> > "in the clouds".
>> >> >
>> >> > If you remember the old cards with rows of holes around the perimeter
>> >> that
>> >> > you could tag with a "V" punch or not, then sort with a rod.
>> >> >
>> >> > The cards could have recipies or pics on them. That is the sort of
>> >> thing
>> >> > I'm looking for, but w/o the physical cards.
>> >> >
>> >> > Essentially a database that links well to image files. I want
>> >> something
>> >> > that could be used for something like objectives so I can sort by
>> >> maker,
>> >> > Mag, NA, tube length and make a page that has images of them in order
>> >> of
>> >> > NA for example.
>> >> >
>> >> > I'm looking for a simple image database program to organize pics in
>> >> > various ways, without having to store the images multiple times (which
>> >> > would do the job).
>> >> >
>> >> > Best,
>> >> >
>> >> > -John
>> >>
>> >>
>> >>
>> >>
>> >> [Non-text portions of this message have been removed]
>> >>
>> >
>> >
>> >
>> >
>> > [Non-text portions of this message have been removed]
>> >
>> >
>>
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

#67772 From: Mark Burgess <fwalgae@...>
Date: Fri Apr 13, 2012 1:24 pm
Subject: Re: Re: Organizing Images
edlnhsnews
Send Email Send Email
 
Picasa van handle RAW files now.

cheers

Mark

On 12 April 2012 14:48, Jaava53 <jaava53@...> wrote:
> I think picasa handles well all the basic picture file formats (bmp, jpg, tiff
- this is best to verify from picasa specs) but it cannot handle raw-files
downloaded from camera. At least couldnt few years ago.
>
> I think Picasa is worth to give a shot.
>
> Jaava
>
>
> --- In Microscope@yahoogroups.com, "J. Forster" <jfor@...> wrote:
>>
>> My files are mostly 100K class .jpgs, but there are also some .bmps
>>
>> -John
>>
>> ================
>>
>>
>> > Scanned in images can be saved to TIFF but imported images are all saved
>> > to jpg as you say. Â
>> >
>> >
>> > ________________________________
>> >  From: Jaava53 <jaava53@...>
>> > To: Microscope@yahoogroups.com
>> > Sent: Wednesday, April 11, 2012 11:12 AM
>> > Subject: [Microscope] Re: Organizing Images
>> >
>> >
>> > Â
>> > I like Picasa too, if jpg pixel size is enough for you.
>> > It saves the pics only once, and then you can create albums wich uses your
>> > pics. You can olso make quieries to your pics using date, camera etc. info
>> > in the EXIF data of the pictures.
>> > You do not need to have a net connection when using Picasa, but it has
>> > means to save your pics into net as well.
>> > My wife likes Picasa too, but I have to use a program having a bit more
>> > bit depth for pixels and post processing abilities (Lightroom - not
>> > freeware).
>> >
>> > --- In Microscope@yahoogroups.com, Roger Moretz <stamptrain@> wrote:
>> >>
>> >> As was mentioned earlier, Picasa 3 is a good database but you have to
>> >> organize everything yourself.  Adobe Photoshop Elements is also good
>> >> and costs about $100.  I have played w/both, don't have a preference.
>> >> RogerÂÂ
>> >>
>> >>
>> >> ________________________________
>> >>  From: Microscopeman <microscopeman@>
>> >> To: Microscope@yahoogroups.com
>> >> Sent: Tuesday, April 10, 2012 4:22 PM
>> >> Subject: Re: [Microscope] Organizing Images
>> >>
>> >>
>> >> ÂÂ
>> >> John,
>> >>
>> >> PAXit!, without any measurement or analysis modules (which are options),
>> >> is
>> >> often deployed for "database only" requirements.
>> >>
>> >> It clearly is not freeware.  I'm not aware of any freeware image
>> >> database
>> >> solutions, sorry.
>> >>
>> >> Good luck,
>> >>
>> >> Gregg
>> >>
>> >> ----- Original Message -----
>> >> From: "J. Forster" <jfor@>
>> >> To: <Microscope@yahoogroups.com>
>> >> Sent: Tuesday, April 10, 2012 12:36 PM
>> >> Subject: Re: [Microscope] Organizing Images
>> >>
>> >> > Thanks, but I have no need to analyze the images. I want something,
>> >> very
>> >> > preferably freeware, resident on my PC essentially, to catalog images
>> >> of
>> >> > stuff, sorted in various ways. I am absolutely not interested in
>> >> anything
>> >> > "in the clouds".
>> >> >
>> >> > If you remember the old cards with rows of holes around the perimeter
>> >> that
>> >> > you could tag with a "V" punch or not, then sort with a rod.
>> >> >
>> >> > The cards could have recipies or pics on them. That is the sort of
>> >> thing
>> >> > I'm looking for, but w/o the physical cards.
>> >> >
>> >> > Essentially a database that links well to image files. I want
>> >> something
>> >> > that could be used for something like objectives so I can sort by
>> >> maker,
>> >> > Mag, NA, tube length and make a page that has images of them in order
>> >> of
>> >> > NA for example.
>> >> >
>> >> > I'm looking for a simple image database program to organize pics in
>> >> > various ways, without having to store the images multiple times (which
>> >> > would do the job).
>> >> >
>> >> > Best,
>> >> >
>> >> > -John
>> >>
>> >>
>> >>
>> >>
>> >> [Non-text portions of this message have been removed]
>> >>
>> >
>> >
>> >
>> >
>> > [Non-text portions of this message have been removed]
>> >
>> >
>>
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

#67773 From: Tom Watson <error253@...>
Date: Fri Apr 13, 2012 2:38 pm
Subject: Re: Re: Organizing Images
error253
Send Email Send Email
 
You might try the GIMP for photoshop-like features. You can perform many
optimizations for size with GIMP, and it is free. GNU Image Manipulation
Program.

My wife is a professional graphic designer (BFA) and hates GIMP, favoring the
full ($$$) Adobe suite, but when times were rough, she used GIMP too(college ate
her money lol). I would write small apps to perform image manipulations for her,
if needed.

I use GIMP all of the time for my website, and you can easily download and
manipulate the source code, if desired, to add functionality.

Gimp.org

Side note about college,
d $/d education ~ -k$    lol

Sent from my iPad

On Apr 13, 2012, at 9:24 AM, Mark Burgess <fwalgae@...> wrote:

> Picasa can handle RAW files now.
>
> cheers
>
> On 12 April 2012 14:48, Jaava53 <jaava53@...> wrote:
>> I think picasa handles well all the basic picture file formats (bmp, jpg,
tiff - this is best to verify from picasa specs) but it cannot handle raw-files
downloaded from camera. At least couldnt few years ago.
>>
>> I think Picasa is worth to give a shot.
>>
>> Jaava
>>
>>
>> --- In Microscope@yahoogroups.com, "J. Forster" <jfor@...> wrote:
>>>
>>> My files are mostly 100K class .jpgs, but there are also some .bmps
>>>
>>> -John
>>>
>>> ================
>>>
>>>
>>>> Scanned in images can be saved to TIFF but imported images are all saved
>>>> to jpg as you say. Â
>>>>
>>>>
>>>> ________________________________
>>>>  From: Jaava53 <jaava53@...>
>>>> To: Microscope@yahoogroups.com
>>>> Sent: Wednesday, April 11, 2012 11:12 AM
>>>> Subject: [Microscope] Re: Organizing Images
>>>>
>>>>
>>>> Â
>>>> I like Picasa too, if jpg pixel size is enough for you.
>>>> It saves the pics only once, and then you can create albums wich uses your
>>>> pics. You can olso make quieries to your pics using date, camera etc. info
>>>> in the EXIF data of the pictures.
>>>> You do not need to have a net connection when using Picasa, but it has
>>>> means to save your pics into net as well.
>>>> My wife likes Picasa too, but I have to use a program having a bit more
>>>> bit depth for pixels and post processing abilities (Lightroom - not
>>>> freeware).
>>>>
>>>> --- In Microscope@yahoogroups.com, Roger Moretz <stamptrain@> wrote:
>>>>>
>>>>> As was mentioned earlier, Picasa 3 is a good database but you have to
>>>>> organize everything yourself.  Adobe Photoshop Elements is also
good
>>>>> and costs about $100.  I have played w/both, don't have a
preference.
>>>>> RogerÂÂ
>>>>>
>>>>>
>>>>> ________________________________
>>>>>  From: Microscopeman <microscopeman@>
>>>>> To: Microscope@yahoogroups.com
>>>>> Sent: Tuesday, April 10, 2012 4:22 PM
>>>>> Subject: Re: [Microscope] Organizing Images
>>>>>
>>>>>
>>>>> ÂÂ
>>>>> John,
>>>>>
>>>>> PAXit!, without any measurement or analysis modules (which are options),
>>>>> is
>>>>> often deployed for "database only" requirements.
>>>>>
>>>>> It clearly is not freeware.  I'm not aware of any freeware image
>>>>> database
>>>>> solutions, sorry.
>>>>>
>>>>> Good luck,
>>>>>
>>>>> Gregg
>>>>>
>>>>> ----- Original Message -----
>>>>> From: "J. Forster" <jfor@>
>>>>> To: <Microscope@yahoogroups.com>
>>>>> Sent: Tuesday, April 10, 2012 12:36 PM
>>>>> Subject: Re: [Microscope] Organizing Images
>>>>>
>>>>>> Thanks, but I have no need to analyze the images. I want something,
>>>>> very
>>>>>> preferably freeware, resident on my PC essentially, to catalog images
>>>>> of
>>>>>> stuff, sorted in various ways. I am absolutely not interested in
>>>>> anything
>>>>>> "in the clouds".
>>>>>>
>>>>>> If you remember the old cards with rows of holes around the perimeter
>>>>> that
>>>>>> you could tag with a "V" punch or not, then sort with a rod.
>>>>>>
>>>>>> The cards could have recipies or pics on them. That is the sort of
>>>>> thing
>>>>>> I'm looking for, but w/o the physical cards.
>>>>>>
>>>>>> Essentially a database that links well to image files. I want
>>>>> something
>>>>>> that could be used for something like objectives so I can sort by
>>>>> maker,
>>>>>> Mag, NA, tube length and make a page that has images of them in order
>>>>> of
>>>>>> NA for example.
>>>>>>
>>>>>> I'm looking for a simple image database program to organize pics in
>>>>>> various ways, without having to store the images multiple times (which
>>>>>> would do the job).
>>>>>>
>>>>>> Best,
>>>>>>
>>>>>> -John
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> [Non-text portions of this message have been removed]
>>>>>
>>>>
>>>>
>>>>
>>>>
>>>> [Non-text portions of this message have been removed]
>>>>
>>>>
>>>
>>
>>
>>
>>
>> ------------------------------------
>>
>> Yahoo! Groups Links
>>
>>
>>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>

#67774 From: "merv" <merv.hobden@...>
Date: Fri Apr 13, 2012 6:54 pm
Subject: Re: Gamma Sterilization with Commercial Source, Part 1
mervhob
Send Email Send Email
 
Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic streptococci never did anyone any harm....)I also
use an electric steamer for odd sterilzation tasks - cheap and cheerful from
ASDA (the British Wally-store). Wet sterilization is also ideal for pipettes,
even small ones. Polypropylene should also be okay with wet steam. And if the
memsahib happens to come into the kitchen at the critical moment? - 'Just
knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological cultures
and especially whenever autoclaving will be done. Even my 96-well plates used
for ELISA or for microbiological analysis (coliform, etc.) are of PP and
withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.  
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

#67775 From: "Fred" <Fred@...>
Date: Fri Apr 13, 2012 7:05 pm
Subject: Re: Gamma Sterilization with Commercial Source, Part 1
fred.hebard
Send Email Send Email
 
I used a pressure canner for professional sterilization for many years.  Just be
careful when you remove the top.  Even with pressure equalized you get a venting
of steam if the vessel is still hot.  Also, media can be super heated (above
boiling point), and will vaporize almost explosively.  So don't put your palm
over the flask when removing from the canner.  We used to stuff about 5 1-liter
flasks into one, with several akimbo on top of the others.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological cultures
and especially whenever autoclaving will be done. Even my 96-well plates used
for ELISA or for microbiological analysis (coliform, etc.) are of PP and
withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.  
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

#67776 From: "Fred" <Fred@...>
Date: Fri Apr 13, 2012 7:06 pm
Subject: Re: Gamma Sterilization with Commercial Source, Part 1
fred.hebard
Send Email Send Email
 
The pressure canner was for home use, by the way, on top of the stove.

#67777 From: Charles Guevara <icecilliate123@...>
Date: Fri Apr 13, 2012 7:22 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
   Hi, Fred...actually they still sell a 'souped up' kitchen pressure cooker
for field sterilization of dental and medical reuseable instruments.
 
   My kitchen pressure cooker(complete with temp guage/safety pressure vale)
was under $45 USD new...very handy for getting agar nutrient tubes, petri
dishes, etc....prepared in short time...then use when needed.   just a shout
out for a very handy hobbyist device!   charlie guevara


________________________________
From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 3:05 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

I used a pressure canner for professional sterilization for many years.  Just
be careful when you remove the top.  Even with pressure equalized you get a
venting of steam if the vessel is still hot.  Also, media can be super heated
(above boiling point), and will vaporize almost explosively.  So don't put your
palm over the flask when removing from the canner.  We used to stuff about 5
1-liter flasks into one, with several akimbo on top of the others.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>




------------------------------------

Yahoo! Groups Links



[Non-text portions of this message have been removed]

#67778 From: Charles Guevara <icecilliate123@...>
Date: Fri Apr 13, 2012 7:34 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
   Thanks for that Merv!  I've actually been told some healthfood stores sell
a type of 'agar'..so merge of kitchen time/stove top media prep may be loosely
construed as food-prep to the intrested /aghast spouse.
 
   I never did find a health food store which sells agar.   charlie
guevara 


________________________________
From: merv <merv.hobden@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 2:54 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1



Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
  streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>




------------------------------------

Yahoo! Groups Links



[Non-text portions of this message have been removed]

#67779 From: Seth Malovany <enigmaseth@...>
Date: Fri Apr 13, 2012 8:21 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
enigmaseth
Send Email Send Email
 
Group;
On the clean side, we in the lab were always trying to get rid of nasty stuff. I
had a friend in Clean Medical supply. What they would do is wrap items,
instruments, etc, in paper or those cotton blue surgical drapes and TAPE
closed with a special masking tape that when exposed to 212 deg F and 15
lbs/sq in pressure for 15 min produces a black line. I am pretty sure you can
get this stuff SOMEWHERE and would give you an INDICATION of sterility as long
as sys (wrap) is still closed. 
With Respect
Seth Malovany MT AMT

--- On Fri, 4/13/12, Charles Guevara <icecilliate123@...> wrote:


From: Charles Guevara <icecilliate123@...>
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Date: Friday, April 13, 2012, 3:22 PM


   Hi, Fred...actually they still sell a 'souped up' kitchen pressure cooker
for field sterilization of dental and medical reuseable instruments.
 
   My kitchen pressure cooker(complete with temp guage/safety pressure vale)
was under $45 USD new...very handy for getting agar nutrient tubes, petri
dishes, etc....prepared in short time...then use when needed.   just a shout
out for a very handy hobbyist device!   charlie guevara


________________________________
From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 3:05 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

I used a pressure canner for professional sterilization for many years.  Just
be careful when you remove the top.  Even with pressure equalized you get a
venting of steam if the vessel is still hot.  Also, media can be super heated
(above boiling point), and will vaporize almost explosively.  So don't put your
palm over the flask when removing from the canner.  We used to stuff about 5
1-liter flasks into one, with several akimbo on top of the others.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>




------------------------------------

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[Non-text portions of this message have been removed]



------------------------------------

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[Non-text portions of this message have been removed]

#67780 From: Ricardo Tsukamoto <rictsuk@...>
Date: Fri Apr 13, 2012 8:23 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
rictsuk
Send Email Send Email
 
Charlie,

You wouldn´t probably find agar in food shops by that name. Agar-agar is used
almost exclusively used in the Japanese culinary. So, go online or to an Asian
grocery and ask for KANTEN. That is pure agar !

Regards,
Ricardo


________________________________
  From: Charles Guevara <icecilliate123@...>
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Sent: Friday, April 13, 2012 4:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 


   Thanks for that Merv!  I've actually been told some healthfood stores sell
a type of 'agar'..so merge of kitchen time/stove top media prep may be loosely
construed as food-prep to the intrested /aghast spouse.
 
   I never did find a health food store which sells agar.   charlie
guevara 

________________________________
From: merv <merv.hobden@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 2:54 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

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[Non-text portions of this message have been removed]




[Non-text portions of this message have been removed]

#67781 From: Seth Malovany <enigmaseth@...>
Date: Fri Apr 13, 2012 8:27 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
enigmaseth
Send Email Send Email
 
Ricardo:
I don't plan on making media anytime soon here but REALLY good to know, THANK
YOU.
I have some Japaneese friends in America I WILL ask them.
With Respect
Seth Malovany MT AMT

--- On Fri, 4/13/12, Ricardo Tsukamoto <rictsuk@...> wrote:


From: Ricardo Tsukamoto <rictsuk@...>
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Date: Friday, April 13, 2012, 4:23 PM


Charlie,

You wouldn´t probably find agar in food shops by that name. Agar-agar is used
almost exclusively used in the Japanese culinary. So, go online or to an Asian
grocery and ask for KANTEN. That is pure agar !

Regards,
Ricardo


________________________________
From: Charles Guevara <icecilliate123@...>
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Sent: Friday, April 13, 2012 4:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 


   Thanks for that Merv!  I've actually been told some healthfood stores sell
a type of 'agar'..so merge of kitchen time/stove top media prep may be loosely
construed as food-prep to the intrested /aghast spouse.
 
   I never did find a health food store which sells agar.   charlie
guevara 

________________________________
From: merv <merv.hobden@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 2:54 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

Yahoo! Groups Links

[Non-text portions of this message have been removed]




[Non-text portions of this message have been removed]



------------------------------------

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[Non-text portions of this message have been removed]

#67782 From: Ricardo Tsukamoto <rictsuk@...>
Date: Fri Apr 13, 2012 8:34 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
rictsuk
Send Email Send Email
 
Seth,

Such sterilization indicator strips can be found in suppliers
like http://yourcleanroomsupplier.com/supplies-equipment/167

But it can be also be homemade of anything that will melt at 120C (common
sterilization) or 134C (hospital sterilization standard). A piece of the melting
material is usually introduced into a short glass tube (i.e. Pasteur pipette
segment) and that tube is sterilized together with the lab materials. If the
subject has melted into another form, it means the hot temperature was kept for
sufficient time to melt that down,and so OK for your treatment.

Regards,
Ricardo


________________________________
  From: Seth Malovany <enigmaseth@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 5:21 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 
Group;
On the clean side, we in the lab were always trying to get rid of nasty stuff. I
had a friend in Clean Medical supply. What they would do is wrap items,
instruments, etc, in paper or those cotton blue surgical drapes and TAPE
closed with a special masking tape that when exposed to 212 deg F and 15
lbs/sq in pressure for 15 min produces a black line. I am pretty sure you can
get this stuff SOMEWHERE and would give you an INDICATION of sterility as long
as sys (wrap) is still closed. 
With Respect
Seth Malovany MT AMT

--- On Fri, 4/13/12, Charles Guevara <icecilliate123@...> wrote:

From: Charles Guevara <icecilliate123@...>
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Date: Friday, April 13, 2012, 3:22 PM

   Hi, Fred...actually they still sell a 'souped up' kitchen pressure cooker
for field sterilization of dental and medical reuseable instruments.
 
   My kitchen pressure cooker(complete with temp guage/safety pressure vale)
was under $45 USD new...very handy for getting agar nutrient tubes, petri
dishes, etc....prepared in short time...then use when needed.   just a shout
out for a very handy hobbyist device!   charlie guevara

________________________________
From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 3:05 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

I used a pressure canner for professional sterilization for many years.  Just
be careful when you remove the top.  Even with pressure equalized you get a
venting of steam if the vessel is still hot.  Also, media can be super heated
(above boiling point), and will vaporize almost explosively.  So don't put your
palm over the flask when removing from the canner.  We used to stuff about 5
1-liter flasks into one, with several akimbo on top of the others.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

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[Non-text portions of this message have been removed]

------------------------------------

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[Non-text portions of this message have been removed]




[Non-text portions of this message have been removed]

#67783 From: "Fred" <Fred@...>
Date: Fri Apr 13, 2012 9:12 pm
Subject: Re: Gamma Sterilization with Commercial Source, Part 1
fred.hebard
Send Email Send Email
 
The following sounds reliable with regard to the discovery of the usefulness of
agar-agar for microbiology.  The source is:
http://hardydiagnostics.com/articles/Agar-and-Fanny-Hesse01.pdf

"All this changed in 1881, when Walter Hesse and his wife, Fanny, joined Koch's
lab in Germany. Her full maiden name was Fanny Angelina Eilshemius, a
German-American born in New York City. Walter was studying airborne
microorganisms, and Fanny assisted him in the lab where she drew beautiful
illustrations of what they saw in the microscope.
One day in 1881, while eating lunch, Walter asked Fanny about the jellies and
puddings that she made and how they managed to stay gelled even in warm weather.
Fannie told him about how she learned about the seaweed product, agar-agar, from
a Dutch neighbor of hers while shewas growing up in New York City. Her neighbor
had emigrated from Indonesia, where it was the local custom to use agar in their
cooking. Fannie suggested that they try this out in their laboratory."

Agar-agar is used in countries additional to Indonesia, including China, and
usually can be purchased in oriental food stores.  It would have wandered into
healthfood cuisine  with other oriental dishes.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>
>
>    Thanks for that Merv!  I've actually been told some healthfood stores
sell a type of 'agar'..so merge of kitchen time/stove top media prep may be
loosely construed as food-prep to the intrested /aghast spouse.
>  
>    I never did find a health food store which sells agar.   charlie
guevara 
>
>
> ________________________________
> From: merv <merv.hobden@...>
> To: Microscope@yahoogroups.com
> Sent: Friday, April 13, 2012 2:54 PM
> Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
>
>
>
> Hi Charles,
>
> Wet steam sterilzation at 100degC is by far the safest option for an amateur,
as was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
>  streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'
>
> Cheers,
>
> Merv
>
> --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@> wrote:
> >
> >    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
> >
> >
> >
> > ________________________________
> > From: Ricardo Tsukamoto <rictsuk@>
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Sent: Wednesday, April 11, 2012 11:34 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> > Seth,
> >
> > Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
> >
> > Another advantage of PP is that it does not receive any chemical
plasticizers during manufacturing as in PVC & polycarbonate - which make them
female inducing (endocrine disruptors). PP has no toxicity and is also also
resistant to most chemicals (acids, bases, salts & organics).
> >
> > For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
> >
> > Soda-lime glass was said to be a risk for aquatic cultures because - when
new - because it slowly leaches sodium carbonate into the water, turning it
basic. Aftersome use of the glass that risk is eliminated. But my feeling is
that such fear is an old time story, when glass was made more empirically and
the raw-materials control  almost unexisted. Present day glass factories are
huge and extremely technical; they wouldn´t waste chemicals or risk
production. We once tested such "alcalinization risk" with new aquariums - now
entirely made of soda-lime glass and some silicone adhesive; there was no pH
shift in a month.  
> >
> > Regards,
> > Ricardo
> >
> >
> > ________________________________
> > From: Seth Malovany <enigmaseth@>
> > To: Microscope@yahoogroups.com
> > Sent: Wednesday, April 11, 2012 8:27 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> >
> >  
> > Tom:
> > Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> > With Respect
> > Seth Malovany MT AMT
> >
> > --- On Wed, 4/11/12, Tom Watson <error253@> wrote:
> >
> > From: Tom Watson <error253@>
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Date: Wednesday, April 11, 2012, 6:46 PM
> >
> > Wow!
> >
> > Tom's bubble is doth burst!
> >
> > Well, truth is truth.
> >
> > I will call Pyrex up tomorrow and let them have it (for what ever good it
will do). When you sell something using a special name which indicates a
material, it carries certain expectations. If you buy something which claims to
be made of Teflon, you expect it to be polytetrafluoroethylene, not some knock
off!
> >
> > Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
> >
> > Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
> >
> > Sent from my iPad
> >
> > On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@> wrote:
> >
> > > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > > instead of borosilicate. Read the information on the plastic top. In
> > > my opinion, this is is just one example how industry does a nice job
> > > deceiving us.
> > >
> > > http://en.wikipedia.org/wiki/Pyrex
> > >
> > > Especially check the last two paragraphs under COMPOSITION.
> > >
> > > Fred
> > >
> > > >
> > > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > > plastic top. Super great deal and they make great petri dishes lol
> > >
> > >
> > >
> > >
> > > TODAY(Beta) • Powered by Yahoo!
> > > Woman goes under the knife for royal look
> > > Privacy Policy
> > >
> > > 
> >
> > [Non-text portions of this message have been removed]
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

#67784 From: "J. Forster" <jfor@...>
Date: Fri Apr 13, 2012 9:23 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
j_forster911
Send Email Send Email
 
Electrologists (permsanent hair removal) use tabletop autoclaves to
sterilize needles and have sterilization witness cards to ensure proper
disinfection.

Try an Electrologist supply place.

-John

===============



> Group;
> On the clean side, we in the lab were always trying to get rid of nasty
> stuff. I had a friend in Clean Medical supply. What they would do is wrap
> items, instruments, etc, in paper or those cotton blue surgical
> drapes and TAPE closed with a special masking tape that when exposed to
> 212 deg F and 15 lbs/sq in pressure for 15 min produces a black line. I
> am pretty sure you can get this stuff SOMEWHERE and would give you an
> INDICATION of sterility as long as sys (wrap) is still closed. 
> With Respect
> Seth Malovany MT AMT
>
> --- On Fri, 4/13/12, Charles Guevara <icecilliate123@...> wrote:
>
>
> From: Charles Guevara <icecilliate123@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
> Part 1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Friday, April 13, 2012, 3:22 PM
>
>
>    Hi, Fred...actually they still sell a 'souped up' kitchen pressure
> cooker for field sterilization of dental and medical reuseable
> instruments.
>  
>    My kitchen pressure cooker(complete with temp guage/safety pressure
> vale) was under $45 USD new...very handy for getting agar nutrient tubes,
> petri dishes, etc....prepared in short time...then use when needed.  
> just a shout out for a very handy hobbyist device!   charlie guevara
>
>
> ________________________________
> From: Fred <Fred@...>
> To: Microscope@yahoogroups.com
> Sent: Friday, April 13, 2012 3:05 PM
> Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
> 1
>
> I used a pressure canner for professional sterilization for many years. 
> Just be careful when you remove the top.  Even with pressure equalized
> you get a venting of steam if the vessel is still hot.  Also, media can
> be super heated (above boiling point), and will vaporize almost
> explosively.  So don't put your palm over the flask when removing from
> the canner.  We used to stuff about 5 1-liter flasks into one, with
> several akimbo on top of the others.
>
> --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...>
> wrote:
>>
>>    For excellent hobbyist sterilization of glassware/agar
>> media/stock solutions...I purchased  a very lowcost 'kitchen
>> steam-cooker'...just a thought  for all in this thread I just caught
>> up with!  charlie guevara
>>
>>
>>
>> ________________________________
>> From: Ricardo Tsukamoto <rictsuk@...>
>> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
>> Sent: Wednesday, April 11, 2012 11:34 PM
>> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial
>> Source, Part 1
>>
>> Seth,
>>
>> Polypropilene can be autoclaved many times without degrading. Most
>> Tupperware-like vessels nowadays are made of polypropilene, so as to
>> make them usable from freezer to microwave oven (BTW, oil & fat may
>> reach temperatures higher than autoclave in the microwave oven).
>> Polypropilene materials can be easily recognized by their recycling
>> number 5 or abbreviation PP, mandatorily written in each vessel.
>>
>> Another advantage of PP is that it does not receive any chemical
>> plasticizers during manufacturing as in PVC & polycarbonate - which make
>> them female inducing (endocrine disruptors). PP has no toxicity and is
>> also also resistant to most chemicals (acids, bases, salts & organics).
>>
>> For more than two decades I´ve been using PP vessels for biological
>> cultures and especially whenever autoclaving will be done. Even my
>> 96-well plates used for ELISA or for microbiological analysis (coliform,
>> etc.) are of PP and withstand a long time in use.
>>
>> Soda-lime glass was said to be a risk for aquatic cultures because -
>> when new - because it slowly leaches sodium carbonate into the water,
>> turning it basic. Aftersome use of the glass that risk is eliminated.
>> But my feeling is that such fear is an old time story, when glass was
>> made more empirically and the raw-materials control  almost
>> unexisted. Present day glass factories are huge and extremely technical;
>> they wouldn´t waste chemicals or risk production. We once tested such
>> "alcalinization risk" with new aquariums - now entirely made of
>> soda-lime glass and some silicone adhesive; there was no pH shift in a
>> month.  
>>
>> Regards,
>> Ricardo
>>
>>
>> ________________________________
>> From: Seth Malovany <enigmaseth@...>
>> To: Microscope@yahoogroups.com
>> Sent: Wednesday, April 11, 2012 8:27 PM
>> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial
>> Source, Part 1
>>
>>
>>  
>> Tom:
>> Depends on the organism. There is a microbe, sometimes many that EAT
>> just about anything. We used plastic during most of my career. My guess
>> is that to withstand the autoclave after the culture is finished the
>> glass had better be of a good quality pyrex. Our plastic cultures just
>> shriveled, but were disposable, so it didn't matter.
>> With Respect
>> Seth Malovany MT AMT
>>
>> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>>
>> From: Tom Watson <error253@...>
>> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial
>> Source, Part 1
>> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
>> Date: Wednesday, April 11, 2012, 6:46 PM
>>
>> Wow!
>>
>> Tom's bubble is doth burst!
>>
>> Well, truth is truth.
>>
>> I will call Pyrex up tomorrow and let them have it (for what ever good
>> it will do). When you sell something using a special name which
>> indicates a material, it carries certain expectations. If you buy
>> something which claims to be made of Teflon, you expect it to be
>> polytetrafluoroethylene, not some knock off!
>>
>> Well, they made fine petri dishes and Carolina Biological sells
>> something similar, claiming it is of benefit to the critters.
>>
>> Does anyone here know why soda-lime would be bad for microorganisms, or
>> otherwise, aside from the different thermal properties?
>>
>> Sent from my iPad
>>
>> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>>
>> > Sorry to pop the bubble. They are clear tempered soda-lime glass
>> > instead of borosilicate. Read the information on the plastic top. In
>> > my opinion, this is is just one example how industry does a nice job
>> > deceiving us.
>> >
>> > http://en.wikipedia.org/wiki/Pyrex
>> >
>> > Especially check the last two paragraphs under COMPOSITION.
>> >
>> > Fred
>> >
>> > >
>> > > Also, for those who want cheap petri dishes... Instead of the $$$
>> > > corning ones or something else, you might try Pyrex kitchen glass. I
>> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
>> > > plastic top. Super great deal and they make great petri dishes lol
>> >
>> >
>> >
>> >
>> > TODAY(Beta) • Powered by Yahoo!
>> > Woman goes under the knife for royal look
>> > Privacy Policy
>> >
>> > 
>>
>> [Non-text portions of this message have been removed]
>>
>> ------------------------------------
>>
>> Yahoo! Groups Links
>>
>> [Non-text portions of this message have been removed]
>>
>>
>>
>>
>> [Non-text portions of this message have been removed]
>>
>>
>>
>> ------------------------------------
>>
>> Yahoo! Groups Links
>>
>>
>>
>> [Non-text portions of this message have been removed]
>>
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>
>
> [Non-text portions of this message have been removed]
>
>

#67785 From: "John Roshak" <jroshak@...>
Date: Fri Apr 13, 2012 9:41 pm
Subject: RE: Re: Gamma Sterilization with Commercial Source, Part 1
genre41
Send Email Send Email
 
If there is no local source, try www.bulkfoods.com <http://www.bulkfoods.com/> 
–they sell agar for  20 oz for $31.49, and larger quantitities if needed.



A little goes a long way.



JohnR

   _____

From: Microscope@yahoogroups.com [mailto:Microscope@yahoogroups.com] On Behalf
Of Ricardo Tsukamoto
Sent: Friday, April 13, 2012 2:23 PM
To: Microscope@yahoogroups.com
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1





Charlie,

You wouldn´t probably find agar in food shops by that name. Agar-agar is used
almost exclusively used in the Japanese culinary. So, go online or to an Asian
grocery and ask for KANTEN. That is pure agar !

Regards,
Ricardo

________________________________
From: Charles Guevara <icecilliate123@...
<mailto:icecilliate123%40yahoo.com> >
To: "Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> "
<Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> >
Sent: Friday, April 13, 2012 4:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1




    Thanks for that Merv!  I've actually been told some healthfood stores sell a
type of 'agar'..so merge of kitchen time/stove top media prep may be loosely
construed as food-prep to the intrested /aghast spouse.

    I never did find a health food store which sells agar.   charlie guevara

________________________________
From: merv <merv.hobden@... <mailto:merv.hobden%40ntlworld.com> >
To: Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com>
Sent: Friday, April 13, 2012 2:54 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> ,
Charles Guevara <icecilliate123@...> wrote:
>
> Â Â  For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> "
<Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> >
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month. Â
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com>
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
> Â
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> "
<Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> >
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> >Â
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

Yahoo! Groups Links

[Non-text portions of this message have been removed]

[Non-text portions of this message have been removed]





[Non-text portions of this message have been removed]

#67786 From: "Fred" <Fred@...>
Date: Fri Apr 13, 2012 9:53 pm
Subject: Re: Methylene Blue and UV
fred.hebard
Send Email Send Email
 
Methylene blue is not listed as a fluorochrome in the Leica-Microsystems.com
list.  Wikipedia says:

"Methylene blue should not be confused with methyl blue, another histology
stain, new methylene blue, nor with the methyl violets often used as pH
indicators."

Methyl blue is one of the components of aniline blue.

--- In Microscope@yahoogroups.com, Tom Watson <error253@...> wrote:
>
> It sounds like I can expose the chemical to long wave UV and get a nice
result.
>
> I wonder if it can be used as a scintillation media. I will test this with
alpha, beta, and gamma this weekend.
>
>
> Sent from my iPad
>
> On Apr 12, 2012, at 12:08 AM, "rich_guy_looker" <rich_guy_looker@...> wrote:
>
> > The links below will give you a good idea,
> > as in absorption below 400nm
> > and emission around 640nm.
> >
> > I'd play around with the Ph
> > of the solution your specimen
> > is in to slightly adjust the spectra
> > (normal saline, 9 grams of NaOH (salt)
> > per liter of water, would be a Ph of 5 to 5.5,
> > with distilled water around Ph 7,
> > but will go lower if sitting in air).
> >
> > http://www.stainsfile.info/StainsFile/dyes/52015.htm
> >
> > Basic info-solubility
> >
> > http://www.jim.or.jp/journal/e/pdf3/45/12/3334.pdf
> >
> > Go to "Fig. 4,"
> > On the page in the upper-left, labeled "3336"
> >
> >
http://iopscience.iop.org/1742-6596/182/1/012078/pdf/1742-6596_182_1_012078.pdf
> >
> > Go to section "3.1. UVâ€"VIS spectra,"
> > On the page at the bottom, labeled "2" - Page Number
> >
> > http://omlc.ogi.edu/spectra/mb/index.html
> >
> > http://en.wikipedia.org/wiki/File:Methylene_blue_absorption_spectrum.png
> >
> > http://micro.magnet.fsu.edu/primer/photomicrography/bwstainchart.html
> >
> >
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000100006
> >
> > Rich
> >
> >
>
> [Non-text portions of this message have been removed]
>

#67787 From: Ricardo Tsukamoto <rictsuk@...>
Date: Fri Apr 13, 2012 10:49 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
rictsuk
Send Email Send Email
 
Thanks for the history of agar introduction into microbiology !

I always wondered how such unique product was discovered as a suitable growth
substrate for microorganisms. Any other common gel would not fit, since
traditional food gels are made of substances (starches or proteins) which would
be easily digested by microorganism´s enzymes, thus liquefying the medium. On
the contrary, agar can not be digested by almost all microorganisms.

I believed that agar was found as the solution after an extensive scientific
search. But it turns out that it was found on a single shot, fortuitously !

Regards,
Ricardo


________________________________
  From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 6:12 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 
The following sounds reliable with regard to the discovery of the usefulness of
agar-agar for microbiology.  The source is:
http://hardydiagnostics.com/articles/Agar-and-Fanny-Hesse01.pdf

"All this changed in 1881, when Walter Hesse and his wife, Fanny, joined Koch's
lab in Germany. Her full maiden name was Fanny Angelina Eilshemius, a
German-American born in New York City. Walter was studying airborne
microorganisms, and Fanny assisted him in the lab where she drew beautiful
illustrations of what they saw in the microscope.
One day in 1881, while eating lunch, Walter asked Fanny about the jellies and
puddings that she made and how they managed to stay gelled even in warm weather.
Fannie told him about how she learned about the seaweed product, agar-agar, from
a Dutch neighbor of hers while shewas growing up in New York City. Her neighbor
had emigrated from Indonesia, where it was the local custom to use agar in their
cooking. Fannie suggested that they try this out in their laboratory."

Agar-agar is used in countries additional to Indonesia, including China, and
usually can be purchased in oriental food stores.  It would have wandered into
healthfood cuisine  with other oriental dishes.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>
>
>    Thanks for that Merv!  I've actually been told some healthfood
stores sell a type of 'agar'..so merge of kitchen time/stove top media prep may
be loosely construed as food-prep to the intrested /aghast spouse.
>  
>    I never did find a health food store which sells agar.  
charlie guevara 
>
>
> ________________________________
> From: merv <merv.hobden@...>
> To: Microscope@yahoogroups.com
> Sent: Friday, April 13, 2012 2:54 PM
> Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
>
>
>
> Hi Charles,
>
> Wet steam sterilzation at 100degC is by far the safest option for an amateur,
as was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
>  streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'
>
> Cheers,
>
> Merv
>
> --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@> wrote:
> >
> >    For excellent hobbyist sterilization of glassware/agar
media/stock solutions...I purchased  a very lowcost 'kitchen
steam-cooker'...just a thought  for all in this thread I just caught up
with!  charlie guevara
> >
> >
> >
> > ________________________________
> > From: Ricardo Tsukamoto <rictsuk@>
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Sent: Wednesday, April 11, 2012 11:34 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> > Seth,
> >
> > Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
> >
> > Another advantage of PP is that it does not receive any chemical
plasticizers during manufacturing as in PVC & polycarbonate - which make them
female inducing (endocrine disruptors). PP has no toxicity and is also also
resistant to most chemicals (acids, bases, salts & organics).
> >
> > For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
> >
> > Soda-lime glass was said to be a risk for aquatic cultures because - when
new - because it slowly leaches sodium carbonate into the water, turning it
basic. Aftersome use of the glass that risk is eliminated. But my feeling is
that such fear is an old time story, when glass was made more empirically and
the raw-materials control  almost unexisted. Present day glass factories
are huge and extremely technical; they wouldn´t waste chemicals or risk
production. We once tested such "alcalinization risk" with new aquariums - now
entirely made of soda-lime glass and some silicone adhesive; there was no pH
shift in a month.  
> >
> > Regards,
> > Ricardo
> >
> >
> > ________________________________
> > From: Seth Malovany <enigmaseth@>
> > To: Microscope@yahoogroups.com
> > Sent: Wednesday, April 11, 2012 8:27 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> >
> >  
> > Tom:
> > Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess
is that to withstand the autoclave after the culture is finished the
glass had better be of a good quality pyrex. Our plastic cultures just
shriveled, but were disposable, so it didn't matter.
> > With Respect
> > Seth Malovany MT AMT
> >
> > --- On Wed, 4/11/12, Tom Watson <error253@> wrote:
> >
> > From: Tom Watson <error253@>
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Date: Wednesday, April 11, 2012, 6:46 PM
> >
> > Wow!
> >
> > Tom's bubble is doth burst!
> >
> > Well, truth is truth.
> >
> > I will call Pyrex up tomorrow and let them have it (for what ever good it
will do). When you sell something using a special name which indicates a
material, it carries certain expectations. If you buy something which claims to
be made of Teflon, you expect it to be polytetrafluoroethylene, not some knock
off!
> >
> > Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
> >
> > Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
> >
> > Sent from my iPad
> >
> > On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@> wrote:
> >
> > > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > > instead of borosilicate. Read the information on the plastic top. In
> > > my opinion, this is is just one example how industry does a nice job
> > > deceiving us.
> > >
> > > http://en.wikipedia.org/wiki/Pyrex
> > >
> > > Especially check the last two paragraphs under COMPOSITION.
> > >
> > > Fred
> > >
> > > >
> > > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > > plastic top. Super great deal and they make great petri dishes lol
> > >
> > >
> > >
> > >
> > > TODAY(Beta) • Powered by Yahoo!
> > > Woman goes under the knife for royal look
> > > Privacy Policy
> > >
> > > 
> >
> > [Non-text portions of this message have been removed]
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>




[Non-text portions of this message have been removed]

#67788 From: "JackC" <jackcheasty@...>
Date: Sat Apr 14, 2012 1:05 am
Subject: Re: Cycloptic 53 wanted
jackcheasty
Send Email Send Email
 
Randall,
I actually have two 53S, one with a dovetail and the other with no dovetail on
its arm.  I just grabbed up a cycloptic on ebay (praying it will be functional,
it has not arrived yet.)  I am now looking to either sell the remaining 53S or
complete it with another cycloptic with the dovetail assembly to attach to its
arm.  I am unfamiliar with the cycloptics and don't know what models will fit on
the 53S.  I enlisted Steve Neeley's able assistance in vetting the one I bought.
Your thoughts? What are the differnces between the 55 and 59?  Can a post mount
rear dovetail be used on either to fit the 53S ?
Jack
--- In Microscope@yahoogroups.com, "Randall Buck" <rbuck@...> wrote:
>
> Hi Jack,
>
> So you already have the 53S with the dovetail and focus adjustment
> knob-pinion gear?
>
> What I mean is, do you need a Cycloptic 55 or 59 (with post mount rear
> dovetail) ?  Or will a more common 56 (with simple stand) be OK?
>
> Randall
>
>
>
> -----Original Message-----
> From: Microscope@yahoogroups.com [mailto:Microscope@yahoogroups.com]On
> Behalf Of JackC
> Sent: Tuesday, April 10, 2012 8:55 PM
> To: Microscope@yahoogroups.com
> Subject: [Microscope] Cycloptic 53 wanted
>
>
> Anyone out there have an AO cycloptic series 53 stereomicroscopr for sale?
> Looking for one to mount on a 53S stand to use on my repair bench to examine
> seats, valves, and fittings.
> Thx,  Jack
> jackcheasty@...
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>

#67789 From: Seth Malovany <enigmaseth@...>
Date: Sat Apr 14, 2012 6:07 am
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
enigmaseth
Send Email Send Email
 
Group:
This is way way off this thread, But I have been reading and hearing about
cognitive scientists working on the "creative process", in a formal and logical
way. What it is, what makes it work etc, using what we know about brain biochem.
In this case the discovery of "agar" was certainly worth a Nobel. And it points
to what some may call providence/luck in how answers/solutions get found. It
also points to communication. THIS GROUP with all its diversity, its quirky
wierdness at times, serves that kind of function.
I have a very good childhood friend who is a THEORETICAL Physicist, who is
always saying to me "show me the math" when I suggest an idea for something.
Sometimes at least in the areas I'm thinking about its a matter of pure dumb
luck, what we call "brute forece" research such as what Edison used to get to a
light bulb filiment. I believe this is the majority of research. My friend
dissagrees. In this case of "agar", there is no math at all, it WAS luck, and
as Ricardo says in his previous posting we ARE , VERY VERY lucky for having
found this seemingly small technical laboratory/experimental improvement. It
opened the possibility for many important discoveries. Cooking!!  Maybe there
is an ART to Science?
With Respect
Seth Malovany MT AMT 

--- On Fri, 4/13/12, Ricardo Tsukamoto <rictsuk@...> wrote:


From: Ricardo Tsukamoto <rictsuk@...>
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Date: Friday, April 13, 2012, 6:49 PM


Thanks for the history of agar introduction into microbiology !

I always wondered how such unique product was discovered as a suitable growth
substrate for microorganisms. Any other common gel would not fit, since
traditional food gels are made of substances (starches or proteins) which would
be easily digested by microorganism´s enzymes, thus liquefying the medium. On
the contrary, agar can not be digested by almost all microorganisms.

I believed that agar was found as the solution after an extensive scientific
search. But it turns out that it was found on a single shot, fortuitously !

Regards,
Ricardo


________________________________
From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 6:12 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 
The following sounds reliable with regard to the discovery of the usefulness of
agar-agar for microbiology.  The source is:
http://hardydiagnostics.com/articles/Agar-and-Fanny-Hesse01.pdf

"All this changed in 1881, when Walter Hesse and his wife, Fanny, joined Koch's
lab in Germany. Her full maiden name was Fanny Angelina Eilshemius, a
German-American born in New York City. Walter was studying airborne
microorganisms, and Fanny assisted him in the lab where she drew beautiful
illustrations of what they saw in the microscope.
One day in 1881, while eating lunch, Walter asked Fanny about the jellies and
puddings that she made and how they managed to stay gelled even in warm weather.
Fannie told him about how she learned about the seaweed product, agar-agar, from
a Dutch neighbor of hers while shewas growing up in New York City. Her neighbor
had emigrated from Indonesia, where it was the local custom to use agar in their
cooking. Fannie suggested that they try this out in their laboratory."

Agar-agar is used in countries additional to Indonesia, including China, and
usually can be purchased in oriental food stores.  It would have wandered into
healthfood cuisine  with other oriental dishes.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>
>
>    Thanks for that Merv!  I've actually been told some healthfood
stores sell a type of 'agar'..so merge of kitchen time/stove top media prep may
be loosely construed as food-prep to the intrested /aghast spouse.
>  
>    I never did find a health food store which sells agar.  
charlie guevara 
>
>
> ________________________________
> From: merv <merv.hobden@...>
> To: Microscope@yahoogroups.com
> Sent: Friday, April 13, 2012 2:54 PM
> Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
>
>
>
> Hi Charles,
>
> Wet steam sterilzation at 100degC is by far the safest option for an amateur,
as was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
>  streptococci never did anyone any harm....)I also use an electric steamer
for odd sterilzation tasks - cheap and cheerful from ASDA (the British
Wally-store). Wet sterilization is also ideal for pipettes, even small ones.
Polypropylene should also be okay with wet steam. And if the memsahib happens to
come into the kitchen at the critical moment? - 'Just knocking up something for
lunch dear.'
>
> Cheers,
>
> Merv
>
> --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@> wrote:
> >
> >    For excellent hobbyist sterilization of glassware/agar
media/stock solutions...I purchased  a very lowcost 'kitchen
steam-cooker'...just a thought  for all in this thread I just caught up
with!  charlie guevara
> >
> >
> >
> > ________________________________
> > From: Ricardo Tsukamoto <rictsuk@>
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Sent: Wednesday, April 11, 2012 11:34 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> > Seth,
> >
> > Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
> >
> > Another advantage of PP is that it does not receive any chemical
plasticizers during manufacturing as in PVC & polycarbonate - which make them
female inducing (endocrine disruptors). PP has no toxicity and is also also
resistant to most chemicals (acids, bases, salts & organics).
> >
> > For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
> >
> > Soda-lime glass was said to be a risk for aquatic cultures because - when
new - because it slowly leaches sodium carbonate into the water, turning it
basic. Aftersome use of the glass that risk is eliminated. But my feeling is
that such fear is an old time story, when glass was made more empirically and
the raw-materials control  almost unexisted. Present day glass factories
are huge and extremely technical; they wouldn´t waste chemicals or risk
production. We once tested such "alcalinization risk" with new aquariums - now
entirely made of soda-lime glass and some silicone adhesive; there was no pH
shift in a month.  
> >
> > Regards,
> > Ricardo
> >
> >
> > ________________________________
> > From: Seth Malovany <enigmaseth@>
> > To: Microscope@yahoogroups.com
> > Sent: Wednesday, April 11, 2012 8:27 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> >
> >  
> > Tom:
> > Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess
is that to withstand the autoclave after the culture is finished the
glass had better be of a good quality pyrex. Our plastic cultures just
shriveled, but were disposable, so it didn't matter.
> > With Respect
> > Seth Malovany MT AMT
> >
> > --- On Wed, 4/11/12, Tom Watson <error253@> wrote:
> >
> > From: Tom Watson <error253@>
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Date: Wednesday, April 11, 2012, 6:46 PM
> >
> > Wow!
> >
> > Tom's bubble is doth burst!
> >
> > Well, truth is truth.
> >
> > I will call Pyrex up tomorrow and let them have it (for what ever good it
will do). When you sell something using a special name which indicates a
material, it carries certain expectations. If you buy something which claims to
be made of Teflon, you expect it to be polytetrafluoroethylene, not some knock
off!
> >
> > Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
> >
> > Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
> >
> > Sent from my iPad
> >
> > On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@> wrote:
> >
> > > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > > instead of borosilicate. Read the information on the plastic top. In
> > > my opinion, this is is just one example how industry does a nice job
> > > deceiving us.
> > >
> > > http://en.wikipedia.org/wiki/Pyrex
> > >
> > > Especially check the last two paragraphs under COMPOSITION.
> > >
> > > Fred
> > >
> > > >
> > > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > > plastic top. Super great deal and they make great petri dishes lol
> > >
> > >
> > >
> > >
> > > TODAY(Beta) • Powered by Yahoo!
> > > Woman goes under the knife for royal look
> > > Privacy Policy
> > >
> > > 
> >
> > [Non-text portions of this message have been removed]
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>




[Non-text portions of this message have been removed]



------------------------------------

Yahoo! Groups Links





[Non-text portions of this message have been removed]

#67790 From: "error253" <error253@...>
Date: Sat Apr 14, 2012 8:50 am
Subject: Re: Methylene Blue and UV
error253
Send Email Send Email
 
I think you are quite correct. I made a solution of 100ml of water and a single
drop of a solution of 0.1% methylene blue. The solution didn't respond in the
visible spectrum to long wave UV, nor did my gamma source show me anything. lol

Well, I bought it for the amoebae!


Amazingly, my first batch of Chaos amoebae were so large that they were visible
with the naked eye. One was perhaps 1/4 to 1/3 mm in length! Amazing little
things.

I'll post some links to pictures and video of them. Amazingly agile for their
"size". lol

--- In Microscope@yahoogroups.com, "Fred" <Fred@...> wrote:
>
> Methylene blue is not listed as a fluorochrome in the Leica-Microsystems.com
list.  Wikipedia says:
>
> "Methylene blue should not be confused with methyl blue, another histology
stain, new methylene blue, nor with the methyl violets often used as pH
indicators."
>
> Methyl blue is one of the components of aniline blue.
>
> --- In Microscope@yahoogroups.com, Tom Watson <error253@> wrote:
> >
> > It sounds like I can expose the chemical to long wave UV and get a nice
result.
> >
> > I wonder if it can be used as a scintillation media. I will test this with
alpha, beta, and gamma this weekend.
> >
> >
> > Sent from my iPad
> >
> > On Apr 12, 2012, at 12:08 AM, "rich_guy_looker" <rich_guy_looker@> wrote:
> >
> > > The links below will give you a good idea,
> > > as in absorption below 400nm
> > > and emission around 640nm.
> > >
> > > I'd play around with the Ph
> > > of the solution your specimen
> > > is in to slightly adjust the spectra
> > > (normal saline, 9 grams of NaOH (salt)
> > > per liter of water, would be a Ph of 5 to 5.5,
> > > with distilled water around Ph 7,
> > > but will go lower if sitting in air).
> > >
> > > http://www.stainsfile.info/StainsFile/dyes/52015.htm
> > >
> > > Basic info-solubility
> > >
> > > http://www.jim.or.jp/journal/e/pdf3/45/12/3334.pdf
> > >
> > > Go to "Fig. 4,"
> > > On the page in the upper-left, labeled "3336"
> > >
> > >
http://iopscience.iop.org/1742-6596/182/1/012078/pdf/1742-6596_182_1_012078.pdf
> > >
> > > Go to section "3.1. UVâ€"VIS spectra,"
> > > On the page at the bottom, labeled "2" - Page Number
> > >
> > > http://omlc.ogi.edu/spectra/mb/index.html
> > >
> > > http://en.wikipedia.org/wiki/File:Methylene_blue_absorption_spectrum.png
> > >
> > > http://micro.magnet.fsu.edu/primer/photomicrography/bwstainchart.html
> > >
> > >
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000100006
> > >
> > > Rich
> > >
> > >
> >
> > [Non-text portions of this message have been removed]
> >
>

#67791 From: "merv" <merv.hobden@...>
Date: Sat Apr 14, 2012 9:16 am
Subject: Re: Gamma Sterilization with Commercial Source, Part 1
mervhob
Send Email Send Email
 
Hi Seth and Group,

Not an irrelevent question, as group interaction is associative not formal. And
this is the characteristic of a parallel machine, not serial, where decisions
are 'weighted', rather than being the result of two things either side of an
equals sign - the basis of algebra! Formal logic and computers are very poor at
associative functions, unless the underlying structures are cast in concrete, as
in mathematics. However, progress in understanding is often intuitive, heuristic
rather than formal. It was once argued that language represented the underlying
structure of intelligence, however, that cannot be correct as there are over
60,000 languages on this planet, and they all do basically the same job.
Language is the means of communicating intelligence, as it is serial - the RS232
interface of intelligence between entities. So this group, and the soggy
parallel machine entities interfacing it 'associate' scraps of information
relating to our subject. The group weights the summation of those scraps,
performing a concensus judgement, which is seldom a 'yes', 'no', 'equals'
formality, but much more fuzzy. Slowly, the group 'learns' more on that subject,
and as it does so, its intelligence increases and convergence next time is more
rapid. Serial machines find such an approach very difficult to replicate - hence
we are superior at tasks such as pattern recognition, which takes serial
computers gigabits to perform succesfully. In a parallel machine, all the 'bits'
are present concurrently, weighted by learning - recognition can be instant! You
don't really want to go through a long, involved sequence of logic if there
might be a tiger close at hand....

Cheers,

Merv

--- In Microscope@yahoogroups.com, Seth Malovany <enigmaseth@...> wrote:
>
>
>
>
>
>
> Group:
> This is way way off this thread, But I have been reading and hearing about
cognitive scientists working on the "creative process", in a formal and logical
way. What it is, what makes it work etc, using what we know about brain biochem.
In this case the discovery of "agar" was certainly worth a Nobel. And it points
to what some may call providence/luck in how answers/solutions get found. It
also points to communication. THIS GROUP with all its diversity, its quirky
wierdness at times, serves that kind of function.
> I have a very good childhood friend who is a THEORETICAL Physicist, who is
always saying to me "show me the math" when I suggest an idea for something.
> Sometimes at least in the areas I'm thinking about its a matter of pure dumb
luck, what we call "brute forece" research such as what Edison used to get to a
light bulb filiment. I believe this is the majority of research. My friend
dissagrees. In this case of "agar", there is no math at all, it WAS luck, and
as Ricardo says in his previous posting we ARE , VERY VERY lucky for having
found this seemingly small technical laboratory/experimental improvement. It
opened the possibility for many important discoveries. Cooking!!  Maybe there
is an ART to Science?
> With Respect
> Seth Malovany MT AMT 
>
> --- On Fri, 4/13/12, Ricardo Tsukamoto <rictsuk@...> wrote:
>
>
> From: Ricardo Tsukamoto <rictsuk@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Friday, April 13, 2012, 6:49 PM
>
>
> Thanks for the history of agar introduction into microbiology !
>
> I always wondered how such unique product was discovered as a suitable growth
substrate for microorganisms. Any other common gel would not fit, since
traditional food gels are made of substances (starches or proteins) which would
be easily digested by microorganism´s enzymes, thus liquefying the medium. On
the contrary, agar can not be digested by almost all microorganisms.
>
> I believed that agar was found as the solution after an extensive scientific
search. But it turns out that it was found on a single shot, fortuitously !
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Fred <Fred@...>
> To: Microscope@yahoogroups.com
> Sent: Friday, April 13, 2012 6:12 PM
> Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
>
>
>  
> The following sounds reliable with regard to the discovery of the usefulness
of agar-agar for microbiology.  The source is:
> http://hardydiagnostics.com/articles/Agar-and-Fanny-Hesse01.pdf
>
> "All this changed in 1881, when Walter Hesse and his wife, Fanny, joined
Koch's lab in Germany. Her full maiden name was Fanny Angelina Eilshemius, a
German-American born in New York City. Walter was studying airborne
microorganisms, and Fanny assisted him in the lab where she drew beautiful
illustrations of what they saw in the microscope.
> One day in 1881, while eating lunch, Walter asked Fanny about the jellies and
puddings that she made and how they managed to stay gelled even in warm weather.
Fannie told him about how she learned about the seaweed product, agar-agar, from
a Dutch neighbor of hers while shewas growing up in New York City. Her neighbor
had emigrated from Indonesia, where it was the local custom to use agar in their
cooking. Fannie suggested that they try this out in their laboratory."
>
> Agar-agar is used in countries additional to Indonesia, including China, and
usually can be purchased in oriental food stores.  It would have wandered into
healthfood cuisine  with other oriental dishes.
>
> --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@> wrote:
> >
> >
> >
> >    Thanks for that Merv!  I've actually been told some healthfood
stores sell a type of 'agar'..so merge of kitchen time/stove top media prep may
be loosely construed as food-prep to the intrested /aghast spouse.
> >  
> >    I never did find a health food store which sells agar.  
charlie guevara 
> >
> >
> > ________________________________
> > From: merv <merv.hobden@>
> > To: Microscope@yahoogroups.com
> > Sent: Friday, April 13, 2012 2:54 PM
> > Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
> >
> >
> >
> > Hi Charles,
> >
> > Wet steam sterilzation at 100degC is by far the safest option for an
amateur, as was shown by Koch, who used a potato steamer. As recounted in my
copy of The Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet
steam was far more effective with sporate organisms than dry heat - 1hr at
100degC in steam was more effective than 3hrs at 140degC dry heat. Growth media
can also be sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
> >  streptococci never did anyone any harm....)I also use an electric steamer
for odd sterilzation tasks - cheap and cheerful from ASDA (the British
Wally-store). Wet sterilization is also ideal for pipettes, even small ones.
Polypropylene should also be okay with wet steam. And if the memsahib happens to
come into the kitchen at the critical moment? - 'Just knocking up something for
lunch dear.'
> >
> > Cheers,
> >
> > Merv
> >
> > --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@> wrote:
> > >
> > >    For excellent hobbyist sterilization of glassware/agar
media/stock solutions...I purchased  a very lowcost 'kitchen
steam-cooker'...just a thought  for all in this thread I just caught up
with!  charlie guevara
> > >
> > >
> > >
> > > ________________________________
> > > From: Ricardo Tsukamoto <rictsuk@>
> > > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > > Sent: Wednesday, April 11, 2012 11:34 PM
> > > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > >
> > > Seth,
> > >
> > > Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
> > >
> > > Another advantage of PP is that it does not receive any chemical
plasticizers during manufacturing as in PVC & polycarbonate - which make them
female inducing (endocrine disruptors). PP has no toxicity and is also also
resistant to most chemicals (acids, bases, salts & organics).
> > >
> > > For more than two decades I´ve been using PP vessels for
biological cultures and especially whenever autoclaving will be done. Even my
96-well plates used for ELISA or for microbiological analysis (coliform, etc.)
are of PP and withstand a long time in use.
> > >
> > > Soda-lime glass was said to be a risk for aquatic cultures because - when
new - because it slowly leaches sodium carbonate into the water, turning it
basic. Aftersome use of the glass that risk is eliminated. But my feeling is
that such fear is an old time story, when glass was made more empirically and
the raw-materials control  almost unexisted. Present day glass factories
are huge and extremely technical; they wouldn´t waste chemicals or risk
production. We once tested such "alcalinization risk" with new aquariums - now
entirely made of soda-lime glass and some silicone adhesive; there was no pH
shift in a month.  
> > >
> > > Regards,
> > > Ricardo
> > >
> > >
> > > ________________________________
> > > From: Seth Malovany <enigmaseth@>
> > > To: Microscope@yahoogroups.com
> > > Sent: Wednesday, April 11, 2012 8:27 PM
> > > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > >
> > >
> > >  
> > > Tom:
> > > Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess
is that to withstand the autoclave after the culture is finished the
glass had better be of a good quality pyrex. Our plastic cultures just
shriveled, but were disposable, so it didn't matter.
> > > With Respect
> > > Seth Malovany MT AMT
> > >
> > > --- On Wed, 4/11/12, Tom Watson <error253@> wrote:
> > >
> > > From: Tom Watson <error253@>
> > > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > > Date: Wednesday, April 11, 2012, 6:46 PM
> > >
> > > Wow!
> > >
> > > Tom's bubble is doth burst!
> > >
> > > Well, truth is truth.
> > >
> > > I will call Pyrex up tomorrow and let them have it (for what ever good it
will do). When you sell something using a special name which indicates a
material, it carries certain expectations. If you buy something which claims to
be made of Teflon, you expect it to be polytetrafluoroethylene, not some knock
off!
> > >
> > > Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
> > >
> > > Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
> > >
> > > Sent from my iPad
> > >
> > > On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@> wrote:
> > >
> > > > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > > > instead of borosilicate. Read the information on the plastic top. In
> > > > my opinion, this is is just one example how industry does a nice job
> > > > deceiving us.
> > > >
> > > > http://en.wikipedia.org/wiki/Pyrex
> > > >
> > > > Especially check the last two paragraphs under COMPOSITION.
> > > >
> > > > Fred
> > > >
> > > > >
> > > > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > > > plastic top. Super great deal and they make great petri dishes lol
> > > >
> > > >
> > > >
> > > >
> > > > TODAY(Beta) • Powered by Yahoo!
> > > > Woman goes under the knife for royal look
> > > > Privacy Policy
> > > >
> > > > 
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > > [Non-text portions of this message have been removed]
> > >
> >
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>
>
> [Non-text portions of this message have been removed]
>

#67792 From: Charles Guevara <icecilliate123@...>
Date: Sat Apr 14, 2012 1:59 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
   Thanks, Ricardo!  now I can try again!   charlie guevara


From: Ricardo Tsukamoto <rictsuk@...>
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Sent: Friday, April 13, 2012 4:23 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Charlie,

You wouldn´t probably find agar in food shops by that name. Agar-agar is used
almost exclusively used in the Japanese culinary. So, go online or to an Asian
grocery and ask for KANTEN. That is pure agar !

Regards,
Ricardo


________________________________
From: Charles Guevara <icecilliate123@...>
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Sent: Friday, April 13, 2012 4:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 


   Thanks for that Merv!  I've actually been told some healthfood stores sell
a type of 'agar'..so merge of kitchen time/stove top media prep may be loosely
construed as food-prep to the intrested /aghast spouse.
 
   I never did find a health food store which sells agar.   charlie
guevara 

________________________________
From: merv <merv.hobden@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 2:54 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

Yahoo! Groups Links

[Non-text portions of this message have been removed]




[Non-text portions of this message have been removed]



------------------------------------

Yahoo! Groups Links



[Non-text portions of this message have been removed]

#67793 From: Charles Guevara <icecilliate123@...>
Date: Sat Apr 14, 2012 2:04 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
  I simply go with the temp/pressure guage on my lowcost cooker...and the time
of the batch in that hellish steam under pressure.
 
But as a hobbyist..standard process log isn't critical ( as in healthcare/food
industry/pharmaceuticals, etc.).  Of course you need strict protocols in
industries.

From: Ricardo Tsukamoto <rictsuk@...>
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Sent: Friday, April 13, 2012 4:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Seth,

Such sterilization indicator strips can be found in suppliers
like http://yourcleanroomsupplier.com/supplies-equipment/167

But it can be also be homemade of anything that will melt at 120C (common
sterilization) or 134C (hospital sterilization standard). A piece of the melting
material is usually introduced into a short glass tube (i.e. Pasteur pipette
segment) and that tube is sterilized together with the lab materials. If the
subject has melted into another form, it means the hot temperature was kept for
sufficient time to melt that down,and so OK for your treatment.

Regards,
Ricardo


________________________________
From: Seth Malovany <enigmaseth@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 5:21 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 
Group;
On the clean side, we in the lab were always trying to get rid of nasty stuff. I
had a friend in Clean Medical supply. What they would do is wrap items,
instruments, etc, in paper or those cotton blue surgical drapes and TAPE
closed with a special masking tape that when exposed to 212 deg F and 15
lbs/sq in pressure for 15 min produces a black line. I am pretty sure you can
get this stuff SOMEWHERE and would give you an INDICATION of sterility as long
as sys (wrap) is still closed. 
With Respect
Seth Malovany MT AMT

--- On Fri, 4/13/12, Charles Guevara <icecilliate123@...> wrote:

From: Charles Guevara <icecilliate123@...>
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
Date: Friday, April 13, 2012, 3:22 PM

   Hi, Fred...actually they still sell a 'souped up' kitchen pressure cooker
for field sterilization of dental and medical reuseable instruments.
 
   My kitchen pressure cooker(complete with temp guage/safety pressure vale)
was under $45 USD new...very handy for getting agar nutrient tubes, petri
dishes, etc....prepared in short time...then use when needed.   just a shout
out for a very handy hobbyist device!   charlie guevara

________________________________
From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 3:05 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

I used a pressure canner for professional sterilization for many years.  Just
be careful when you remove the top.  Even with pressure equalized you get a
venting of steam if the vessel is still hot.  Also, media can be super heated
(above boiling point), and will vaporize almost explosively.  So don't put your
palm over the flask when removing from the canner.  We used to stuff about 5
1-liter flasks into one, with several akimbo on top of the others.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month.
 
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

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[Non-text portions of this message have been removed]

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[Non-text portions of this message have been removed]



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[Non-text portions of this message have been removed]

#67794 From: Charles Guevara <icecilliate123@...>
Date: Sat Apr 14, 2012 2:19 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
Dr. BetseyDexter-Dyer has an audio-book on tape (my car only plays MP3's,
CD's...call that progress...sighh) about our worlds microbial
underpinnings...she mentions that long unappreciated spouse and her
contributions to Dr.Koch's lab team!
 
   Thanks, Fred, for fleshing out that history, and giving us her name, and
the circumstances of her contributions!   charlie guevara

From: Fred <Fred@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 5:12 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

The following sounds reliable with regard to the discovery of the usefulness of
agar-agar for microbiology.  The source is:
http://hardydiagnostics.com/articles/Agar-and-Fanny-Hesse01.pdf

"All this changed in 1881, when Walter Hesse and his wife, Fanny, joined Koch's
lab in Germany. Her full maiden name was Fanny Angelina Eilshemius, a
German-American born in New York City. Walter was studying airborne
microorganisms, and Fanny assisted him in the lab where she drew beautiful
illustrations of what they saw in the microscope.
One day in 1881, while eating lunch, Walter asked Fanny about the jellies and
puddings that she made and how they managed to stay gelled even in warm weather.
Fannie told him about how she learned about the seaweed product, agar-agar, from
a Dutch neighbor of hers while shewas growing up in New York City. Her neighbor
had emigrated from Indonesia, where it was the local custom to use agar in their
cooking. Fannie suggested that they try this out in their laboratory."

Agar-agar is used in countries additional to Indonesia, including China, and
usually can be purchased in oriental food stores.  It would have wandered into
healthfood cuisine  with other oriental dishes.

--- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@...> wrote:
>
>
>
>    Thanks for that Merv!  I've actually been told some healthfood
stores sell a type of 'agar'..so merge of kitchen time/stove top media prep may
be loosely construed as food-prep to the intrested /aghast spouse.
>  
>    I never did find a health food store which sells agar.  
charlie guevara 
>
>
> ________________________________
> From: merv <merv.hobden@...>
> To: Microscope@yahoogroups.com
> Sent: Friday, April 13, 2012 2:54 PM
> Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1
>
>
>
> Hi Charles,
>
> Wet steam sterilzation at 100degC is by far the safest option for an amateur,
as was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
>  streptococci never did anyone any harm....)I also use an electric steamer
for odd sterilzation tasks - cheap and cheerful from ASDA (the British
Wally-store). Wet sterilization is also ideal for pipettes, even small ones.
Polypropylene should also be okay with wet steam. And if the memsahib happens to
come into the kitchen at the critical moment? - 'Just knocking up something for
lunch dear.'
>
> Cheers,
>
> Merv
>
> --- In Microscope@yahoogroups.com, Charles Guevara <icecilliate123@> wrote:
> >
> >    For excellent hobbyist sterilization of glassware/agar
media/stock solutions...I purchased  a very lowcost 'kitchen
steam-cooker'...just a thought  for all in this thread I just caught up
with!  charlie guevara
> >
> >
> >
> > ________________________________
> > From: Ricardo Tsukamoto <rictsuk@>
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Sent: Wednesday, April 11, 2012 11:34 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> > Seth,
> >
> > Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
> >
> > Another advantage of PP is that it does not receive any chemical
plasticizers during manufacturing as in PVC & polycarbonate - which make them
female inducing (endocrine disruptors). PP has no toxicity and is also also
resistant to most chemicals (acids, bases, salts & organics).
> >
> > For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
> >
> > Soda-lime glass was said to be a risk for aquatic cultures because - when
new - because it slowly leaches sodium carbonate into the water, turning it
basic. Aftersome use of the glass that risk is eliminated. But my feeling is
that such fear is an old time story, when glass was made more empirically and
the raw-materials control  almost unexisted. Present day glass factories
are huge and extremely technical; they wouldn´t waste chemicals or risk
production. We once tested such "alcalinization risk" with new aquariums - now
entirely made of soda-lime glass and some silicone adhesive; there was no pH
shift in a month.  
> >
> > Regards,
> > Ricardo
> >
> >
> > ________________________________
> > From: Seth Malovany <enigmaseth@>
> > To: Microscope@yahoogroups.com
> > Sent: Wednesday, April 11, 2012 8:27 PM
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> >
> >
> >  
> > Tom:
> > Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess
is that to withstand the autoclave after the culture is finished the
glass had better be of a good quality pyrex. Our plastic cultures just
shriveled, but were disposable, so it didn't matter.
> > With Respect
> > Seth Malovany MT AMT
> >
> > --- On Wed, 4/11/12, Tom Watson <error253@> wrote:
> >
> > From: Tom Watson <error253@>
> > Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source,
Part 1
> > To: "Microscope@yahoogroups.com" <Microscope@yahoogroups.com>
> > Date: Wednesday, April 11, 2012, 6:46 PM
> >
> > Wow!
> >
> > Tom's bubble is doth burst!
> >
> > Well, truth is truth.
> >
> > I will call Pyrex up tomorrow and let them have it (for what ever good it
will do). When you sell something using a special name which indicates a
material, it carries certain expectations. If you buy something which claims to
be made of Teflon, you expect it to be polytetrafluoroethylene, not some knock
off!
> >
> > Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
> >
> > Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
> >
> > Sent from my iPad
> >
> > On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@> wrote:
> >
> > > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > > instead of borosilicate. Read the information on the plastic top. In
> > > my opinion, this is is just one example how industry does a nice job
> > > deceiving us.
> > >
> > > http://en.wikipedia.org/wiki/Pyrex
> > >
> > > Especially check the last two paragraphs under COMPOSITION.
> > >
> > > Fred
> > >
> > > >
> > > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > > plastic top. Super great deal and they make great petri dishes lol
> > >
> > >
> > >
> > >
> > > TODAY(Beta) • Powered by Yahoo!
> > > Woman goes under the knife for royal look
> > > Privacy Policy
> > >
> > > 
> >
> > [Non-text portions of this message have been removed]
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
> >
> >
> > ------------------------------------
> >
> > Yahoo! Groups Links
> >
> >
> >
> > [Non-text portions of this message have been removed]
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>




------------------------------------

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[Non-text portions of this message have been removed]

#67795 From: Charles Guevara <icecilliate123@...>
Date: Sat Apr 14, 2012 2:21 pm
Subject: Re: Re: Gamma Sterilization with Commercial Source, Part 1
icecilliate123
Send Email Send Email
 
   Thanks, JohnR.  charlie guevara


From: John Roshak <jroshak@...>
To: Microscope@yahoogroups.com
Sent: Friday, April 13, 2012 5:41 PM
Subject: RE: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

If there is no local source, try www.bulkfoods.com <http://www.bulkfoods.com/> 
–they sell agar for  20 oz for $31.49, and larger quantitities if needed.



A little goes a long way.



JohnR

  _____ 

From: Microscope@yahoogroups.com [mailto:Microscope@yahoogroups.com] On Behalf
Of Ricardo Tsukamoto
Sent: Friday, April 13, 2012 2:23 PM
To: Microscope@yahoogroups.com
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1



 

Charlie,

You wouldn´t probably find agar in food shops by that name. Agar-agar is used
almost exclusively used in the Japanese culinary. So, go online or to an Asian
grocery and ask for KANTEN. That is pure agar !

Regards,
Ricardo

________________________________
From: Charles Guevara <icecilliate123@...
<mailto:icecilliate123%40yahoo.com> >
To: "Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> "
<Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> >
Sent: Friday, April 13, 2012 4:34 PM
Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1


 

  Thanks for that Merv!  I've actually been told some healthfood stores sell a
type of 'agar'..so merge of kitchen time/stove top media prep may be loosely
construed as food-prep to the intrested /aghast spouse.

  I never did find a health food store which sells agar.  charlie guevara

________________________________
From: merv <merv.hobden@... <mailto:merv.hobden%40ntlworld.com> >
To: Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> 
Sent: Friday, April 13, 2012 2:54 PM
Subject: [Microscope] Re: Gamma Sterilization with Commercial Source, Part 1

Hi Charles,

Wet steam sterilzation at 100degC is by far the safest option for an amateur, as
was shown by Koch, who used a potato steamer. As recounted in my copy of The
Manual of Bacteriology ( Muir and Ritchie, 1925) Koch found that wet steam was
far more effective with sporate organisms than dry heat - 1hr at 100degC in
steam was more effective than 3hrs at 140degC dry heat. Growth media can also be
sterilised as the wet steam prevents evaporation. Tyndall introduced
intermittant steaming over three days to ensure that all spores were eliminated;
after three days the media will remain sterile indefinitely if sealed.
Glassware, including soda-lime can be sterilized in this way - I generally start
with the water close to boiling - put the glassware in and steam for an hour.
Here a stove top stainless steel steamer is the best option, as you can use dry
heat to finish the process. (The drying cycle of a dishwasher is ideal - a bit
of escherichia coli/haemolytic
streptococci never did anyone any harm....)I also use an electric steamer for
odd sterilzation tasks - cheap and cheerful from ASDA (the British Wally-store).
Wet sterilization is also ideal for pipettes, even small ones. Polypropylene
should also be okay with wet steam. And if the memsahib happens to come into the
kitchen at the critical moment? - 'Just knocking up something for lunch dear.'

Cheers,

Merv

--- In Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> ,
Charles Guevara <icecilliate123@...> wrote:
>
>    For excellent hobbyist sterilization of glassware/agar media/stock
solutions...I purchased  a very lowcost 'kitchen steam-cooker'...just a
thought  for all in this thread I just caught up with!  charlie guevara
>
>
>
> ________________________________
> From: Ricardo Tsukamoto <rictsuk@...>
> To: "Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> "
<Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> >
> Sent: Wednesday, April 11, 2012 11:34 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
> Seth,
>
> Polypropilene can be autoclaved many times without degrading. Most
Tupperware-like vessels nowadays are made of polypropilene, so as to make them
usable from freezer to microwave oven (BTW, oil & fat may reach temperatures
higher than autoclave in the microwave oven). Polypropilene materials can be
easily recognized by their recycling number 5 or abbreviation PP, mandatorily
written in each vessel.
>
> Another advantage of PP is that it does not receive any chemical plasticizers
during manufacturing as in PVC & polycarbonate - which make them female inducing
(endocrine disruptors). PP has no toxicity and is also also resistant to most
chemicals (acids, bases, salts & organics).
>
> For more than two decades I´ve been using PP vessels for biological
cultures and especially whenever autoclaving will be done. Even my 96-well
plates used for ELISA or for microbiological analysis (coliform, etc.) are of PP
and withstand a long time in use.
>
> Soda-lime glass was said to be a risk for aquatic cultures because - when new
- because it slowly leaches sodium carbonate into the water, turning it basic.
Aftersome use of the glass that risk is eliminated. But my feeling is that such
fear is an old time story, when glass was made more empirically and the
raw-materials control  almost unexisted. Present day glass factories are huge
and extremely technical; they wouldn´t waste chemicals or risk production. We
once tested such "alcalinization risk" with new aquariums - now entirely made of
soda-lime glass and some silicone adhesive; there was no pH shift in a month. Â
>
> Regards,
> Ricardo
>
>
> ________________________________
> From: Seth Malovany <enigmaseth@...>
> To: Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> 
> Sent: Wednesday, April 11, 2012 8:27 PM
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
>
>
>  
> Tom:
> Depends on the organism. There is a microbe, sometimes many that EAT just
about anything. We used plastic during most of my career. My guess is that to
withstand the autoclave after the culture is finished the glass had better be of
a good quality pyrex. Our plastic cultures just shriveled, but were disposable,
so it didn't matter.
> With Respect
> Seth Malovany MT AMT
>
> --- On Wed, 4/11/12, Tom Watson <error253@...> wrote:
>
> From: Tom Watson <error253@...>
> Subject: Re: [Microscope] Re: Gamma Sterilization with Commercial Source, Part
1
> To: "Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> "
<Microscope@yahoogroups.com <mailto:Microscope%40yahoogroups.com> >
> Date: Wednesday, April 11, 2012, 6:46 PM
>
> Wow!
>
> Tom's bubble is doth burst!
>
> Well, truth is truth.
>
> I will call Pyrex up tomorrow and let them have it (for what ever good it will
do). When you sell something using a special name which indicates a material, it
carries certain expectations. If you buy something which claims to be made of
Teflon, you expect it to be polytetrafluoroethylene, not some knock off!
>
> Well, they made fine petri dishes and Carolina Biological sells something
similar, claiming it is of benefit to the critters.
>
> Does anyone here know why soda-lime would be bad for microorganisms, or
otherwise, aside from the different thermal properties?
>
> Sent from my iPad
>
> On Apr 11, 2012, at 3:46 PM, Fred Lieberman <quartz@...> wrote:
>
> > Sorry to pop the bubble. They are clear tempered soda-lime glass
> > instead of borosilicate. Read the information on the plastic top. In
> > my opinion, this is is just one example how industry does a nice job
> > deceiving us.
> >
> > http://en.wikipedia.org/wiki/Pyrex
> >
> > Especially check the last two paragraphs under COMPOSITION.
> >
> > Fred
> >
> > >
> > > Also, for those who want cheap petri dishes... Instead of the $$$
> > > corning ones or something else, you might try Pyrex kitchen glass. I
> > > bought a 4 pack at wall-mart for $7. Each is Pyrex glass with a
> > > plastic top. Super great deal and they make great petri dishes lol
> >
> >
> >
> >
> > TODAY(Beta) • Powered by Yahoo!
> > Woman goes under the knife for royal look
> > Privacy Policy
> >
> > 
>
> [Non-text portions of this message have been removed]
>
> ------------------------------------
>
> Yahoo! Groups Links
>
> [Non-text portions of this message have been removed]
>
>
>
>
> [Non-text portions of this message have been removed]
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
> [Non-text portions of this message have been removed]
>

------------------------------------

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[Non-text portions of this message have been removed]

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[Non-text portions of this message have been removed]

#67796 From: "J. Forster" <jfor@...>
Date: Sat Apr 14, 2012 2:20 pm
Subject: ADMIN: Re: Re: Gamma Sterilization with Commercial Source, Part 1
j_forster911
Send Email Send Email
 
PLEASE:

Trim your posts to recent, relevant stuff!

-John

Group Moderator
====================

#67797 From: "Rick" <desertrat2170@...>
Date: Sat Apr 14, 2012 3:33 pm
Subject: Re: Methylene Blue and UV
desertrat2170
Send Email Send Email
 
A research group succeeded in using Methylene blue fluorescence to image lymph
nodes, but they were working in the near infrared as far as I can tell. The full
article is behind a pay wall, but the abstract is here:

http://www.sciencedirect.com/science/article/pii/S1389172308001023

--- In Microscope@yahoogroups.com, "error253" <error253@...> wrote:
>
> I think you are quite correct. I made a solution of 100ml of water and a
single drop of a solution of 0.1% methylene blue. The solution didn't respond in
the visible spectrum to long wave UV, nor did my gamma source show me anything.
lol
>
> Well, I bought it for the amoebae!
>
>
> Amazingly, my first batch of Chaos amoebae were so large that they were
visible with the naked eye. One was perhaps 1/4 to 1/3 mm in length! Amazing
little things.
>
> I'll post some links to pictures and video of them. Amazingly agile for their
"size". lol
>
> --- In Microscope@yahoogroups.com, "Fred" <Fred@> wrote:
> >
> > Methylene blue is not listed as a fluorochrome in the Leica-Microsystems.com
list.  Wikipedia says:
> >
> > "Methylene blue should not be confused with methyl blue, another histology
stain, new methylene blue, nor with the methyl violets often used as pH
indicators."
> >
> > Methyl blue is one of the components of aniline blue.
> >
> > --- In Microscope@yahoogroups.com, Tom Watson <error253@> wrote:
> > >
> > > It sounds like I can expose the chemical to long wave UV and get a nice
result.
> > >
> > > I wonder if it can be used as a scintillation media. I will test this with
alpha, beta, and gamma this weekend.
> > >
> > >
> > > Sent from my iPad
> > >
> > > On Apr 12, 2012, at 12:08 AM, "rich_guy_looker" <rich_guy_looker@> wrote:
> > >
> > > > The links below will give you a good idea,
> > > > as in absorption below 400nm
> > > > and emission around 640nm.
> > > >
> > > > I'd play around with the Ph
> > > > of the solution your specimen
> > > > is in to slightly adjust the spectra
> > > > (normal saline, 9 grams of NaOH (salt)
> > > > per liter of water, would be a Ph of 5 to 5.5,
> > > > with distilled water around Ph 7,
> > > > but will go lower if sitting in air).
> > > >
> > > > http://www.stainsfile.info/StainsFile/dyes/52015.htm
> > > >
> > > > Basic info-solubility
> > > >
> > > > http://www.jim.or.jp/journal/e/pdf3/45/12/3334.pdf
> > > >
> > > > Go to "Fig. 4,"
> > > > On the page in the upper-left, labeled "3336"
> > > >
> > > >
http://iopscience.iop.org/1742-6596/182/1/012078/pdf/1742-6596_182_1_012078.pdf
> > > >
> > > > Go to section "3.1. UVâ€"VIS spectra,"
> > > > On the page at the bottom, labeled "2" - Page Number
> > > >
> > > > http://omlc.ogi.edu/spectra/mb/index.html
> > > >
> > > > http://en.wikipedia.org/wiki/File:Methylene_blue_absorption_spectrum.png
> > > >
> > > > http://micro.magnet.fsu.edu/primer/photomicrography/bwstainchart.html
> > > >
> > > >
http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532009000100006
> > > >
> > > > Rich
> > > >
> > > >
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