Modified technique for periodic acid-Schiff staining of glycoproteins on agarose-film electrophoretograms

Abstract

We have modified the periodic acid-Schiff staining technique for glycoproteins for use with thin agarose-film electrophoresis membranes. With this procedure, carbohydrate-rich proteins can be detected with negligible background staining and insignificant staining of nonglycoproteins such as albumin and nonglycosylated Bence Jones proteins (free light chains). On the other hand, carbohydrate-rich M components of immunoglobulins M and A in serum and in cerebrospinal fluid from patients with plasma cell dyscrasia are readily detected. The technique is 2- to 3-fold more sensitive than Ponceau S. Glycoproteins in serum and body fluids can be determined as a routine analytical procedure.