this is my method to store SDS-PAGE gels for several months:
equilibrate your gels in 4 degrees celcius in two bins containing Transfer Buffer (0.025M tris base,0.192M glycine, 40% MetOH,
10% HOAc - if you are lazy just use plain transfer buffer but will store shorter time) for 15 min.
Pour off excess buffer and freeze the gels.
Carefully thaw gels at room temperature for 30 minutes.
(NOTE DO NOT AGITATE)
Tested with both Biorad mini gels (7cmx10cm) and 16cm x 18cm gels.
Immunostaining, western blot and subsequent blots with HRP and Alkaline phosphatase have worked
consistently even after long storage.
Max Storage: Several months