> antibody and conditions. Predictably it is because of the degradation
> of protein at the storage time. I kept it at -70 degree after the
> solublisation with 5X sample buffer after the lysis and extraction of
> the protein.
Not necessarily due to degradation. Could be irreversible, hard aggregation.
How did you freeze - just stuck the samples at -70 or did you flash-freeze
in liquid N2 (much better results usually).