In article <aldridge-ya023480002301971031250001 at news.unimelb.edu.au>,
aldridge at mbcmr.unimelb.edu.au (David Aldridge) wrote:
> >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?
>> Acrylamide is unstable and will break down, by deamination, to acrylic acid
> in a reaction catalysed by light and alkali. I'm not sure of the details,
> but by checking the pH of and old acrylamide solution will give an
> indication of whether it has broken down yet. Also adding a small amout of
> basic ion exchange resin will help preserve it. You should therefore not
> add the acylamide to your mix until ready to use it. The Tris, water and
> SDS can however be mixed in advance.
I routinely use pre-mixed solutions and they seem to work fine for at
least 4-6 weeks. Admittedly, I usually only run mini-gels and am not too
worried about great resolution. I store them in the dark at 4C.
Neil
