Mass spectral compatibility of four proteomics stains.

With the recent introduction of new fluorescence stains to the proteomics market, there is now more choice available. SYPRO Ruby, LavaPurple, Flamingo, and Krypton total protein stains were compared for ease of use, image quality, and compatibility with protein identification by peptide mass fingerprinting (PMF) (MALDI-TOF). All four stains produced good images but with slightly different staining patterns. SYPRO was found to inhibit identification of cysteine and tryptophan containing peptides, which reduced protein identification.