A Simple Fluorescent Post-labeling Technique with o-Phthalaldehyde for the Analysis of Proteins by Polyacrylamide Gel Electrophoresis

Abstract

A new polyacrylamide gel electrophoretic system with post-labeling of proteins with o-phthalaldehyde (OPT) has been developed. In the present system, the widely used tris, glycine and ammonium persulfate were replaced by triethanolamine, L-hydroxyproline and sodium persulfate, respectively. Proteins were visualized by dipping the gels in the OPT reagent for several minutes immediately after electrophoresis, and the gels were then scanned in a fluorescence densitometer. Fifty nanograms of bovine serum albumin could be detected by this technique.