Mass spectrometric identification of proteins from silver-stained polyacrylamide gel: a method for the removal of silver ions to enhance sensitivity.

Mass spectrometry is a powerful technique for the identification of proteins at nanogram quantities. However, some degree of sample preparation prior to mass spectrometry is required, and silver-stained protein gel samples are most problematic. Here we report our strategy to obtain peptide mass profiles from silver-stained protein gel samples from one- or two-dimensional gels by destaining prior to enzymatic digestion. This study demonstrates that by using the destaining method, the sensitivity and quality of mass spectra is increased for matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometric analysis, permitting more proteins to be identified by peptide mass database analysis.