I think this is a trivial problem, but I have been trying to detect and
resolve a cyclic peptide of mol. wt. 1,300 from a bacterial extract. I
am using a peptide gel recipe for SDS-PAGE based on the Schagger + von
Jagow Tris/Tricine system, that uses a 16% acrylamide resolving gel, a
9.5% acrylamide spacer gel, and a 5% acrylamide stacking gel. I'm
having trouble detecting the peptide (it contains a 35S-Met), but my
question is related to 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,
Paul Phelan
