Can anyone suggest me a protocol for silver-staining the PAGE that is already stained with Coomassie.
There is absolutely nothing wrong with silver staining of a Coomassie-stained gel without destaining. It only prevents "blowout" of most intense bands already well-visible with Coomassie. The only thing to do is to equlibrate the gel in water before going with silver. At least that's my experinece with the silver staining protocol that is based on tungstosilicic acid (aka Bio-Rad Silver Stain Plus described here for DNA in agarose but works equally well for proteins in PAAG: http://www.ncbi.nlm.nih.gov/pubmed/2446526 ).
- Dima
