Fluorescent Staining of Proteins with SYPRO Ruby

INTRODUCTIONSYPRO Ruby is a sensitive ruthenium-based fluorescent dye that, similar to silver stains, interacts with basic amino acids, including lysine, arginine, and histidine. Recent studies have shown that this dye is as sensitive as silver staining and completely compatible with matrix-assisted laser desorption/ionization (MALDI) mass spectroscopy. The staining method has only three steps: fixation, staining, and destaining. Since SYPRO Ruby is very expensive, this dye might be limited to micropreparative gels, as the cost to run the large number of gels done in quantitative studies is prohibitive.