Problems with silverstaining

[Suzanne Hermeling]

Hi,


I have a question. I am working on protein purification and because I
have very low protein concentration I use silverstaining to visualize
the proteins on an SDS-PAGE gel.

But here comes the problem:
One time we have a good pattern of proteins and the other time we have
only a very dark background without any pattern.
Even on the same day when we stain two gels at the same time there is a
big difference .
Has anybody had this experience before or does anybody has a solution
for my problem?

I am looking forward to it.
BTW: I use the silverstain plus kit from BioRad

Thanks.

Suzanne