Cracking 16% acrylamide SDS-PAGE gels

[Dr Engelbert Buxbaum]

Am 02.07.2009, 17:45 Uhr, schrieb DK <dk from no.email.thankstospam.net>:

>> a problem we are having with the gels cracking
>> after they are dried on a gel drier and then frozen at -80 C before
>> being developed on x-ray film.  Most of the time, the gels are cracked
>> after drying, and freeze/thawing just makes the cracking worse.
>> I think the gels are cracking just because they are more brittle at a
>> high acrylamide concentration, but does anyone have any fool-proof
>> tricks for drying thin (0.75 mm) 16% acrylamide mini-gels without
>> cracking them?
>>
>> Any words of wisdom much appreciated,
>
> Equilibrate the gels with 3% glycerol before drying. Then they
> won't crack.

One thing you can try in addition to using glycerol is to dry gels at room  
temperature. You place them between two sheets of wet cellulose acetate  
foil, those you span in a drying frame (BioRad floggs them, but they are  
just two rectangular frames of plastic, about 20 mm wide and 4 or 5 mm  
thick, held together by clamps). Those you put upright in a quiet place  
over night. As the sheets dry they shrink, and you get a flat, translucent  
dried gel that is also easy to rehydrate, if need be. Obviously, for weak  
radiators like 35-S you need to use autofluorography rather than  
autoradiography.