In article <01bc008e$1c29f8c0$0c019386 at schmidtdw.rz.ruhr-uni-bochum.de>,
"Thorsten Schmidt" <Thorsten.Schmidt at rz.ruhr-uni-bochum.de> wrote:
>Dear reader!
>>I make many Western blots and SDS-PAGE-gels.
[snip]
>Is there anything to be said against preparing a 3 % and a 10 % gel-mix
>by mixing the componets (except for APS & TEMED) in advance?
>>It would minimize time by just adding TEMED & APS to a aliquot!
>Or isn´t it good to store such a mix for a longer time?
>>Thank you for your answer
>>Thorsten Schmidt
>Acrylamide hydrolyzes to give acrylic acid. If the monomer hydrolyzes to a
significant extent, your gels will not run correctly - i.e., be different than
older gels run with purer monomer. Thus, for really precise work, older
references suggested making the monomer/cross-linker solutions fresh monthly,
weekly, or even daily. I would guess that preparing the mix at your dilutions
(3% and 10%) would accellerate the hydrolysis.
However, this would be easy to test - prepare a batch and let it set a week or
so, then compare a gel made from the diluted stock to a gel made as you do now
loading with the same samples. Obviously, you can't add the TEMED or APS
until you're ready to cast.
Frankly, I think you'd find it just as easy to acquire "automatic volume"
devices - pipettors - preset to the volumes you want.
Good luck
JCF
