4% Agar?

[Wolfgang Schechinger]

Dear Namjin

How do you remove pressure from your autoclave? Do it as slow as 
possible (In physical terms, the pressure in your autoclav must not 
be lower than the steam pressure of your liquid at it's actual 
temperature (correct me if I'm wrong), otherwise your agar will boil)

BTW. Do you really need to autoclave your agar? Using 
autoclaved water and microwaving might be enough, at least for E. 
coli plates containing amp.

Good luck, 
Wolfgang
> Dear Yeasters,
> 
> I have wanted to make 2X agar (4%) solution, but every time I try I
> get overflow after autoclaving.  First I autoclaved agar in water
> for 20min to make less than 500mL in 2-L erhlenmeyer flask, and I
> got an overflow.  Then, I melted agar with microwave before
> autoclave, and I got another.  Reduced the autoclave time to 15min,
> and I still got an overflow.  What's wrong?  Do I miss something
> everyone else knows?  
> 
> Steamed 
> 
> 
>   ___________________________________
> 
>   Namjin Chung
>   Rm. 213 MSRB, Box 3345
>   Program in Molecular Cancer Biology
>   Duke University Medical Center
>   Durham, NC 27710
>   nc1 at acpub.duke.edu
> 
>   ___________________________________
> 
> 
> 
---------!all possible disclaimers apply!-----------
                                     
Wolfgang Schechinger
University of Tuebingen
email: wgschech at med.uni-tuebingen.de

http://www.medizin.uni-tuebingen.de/~wgschech/research.htm

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