An Improved Periodic Acid Fuchsin Sulfite Staining Method for Evaluation of Glycoproteins

Abstract

Abstract Modification of the Köiw and Grönwall procedure for the staining of glycoproteins separated by paper electrophoresis has adapted this method to papers of the Whatman 3MM class, with achievement of results comparable to those reported by direct chemical determination of hexose in the individual protein fractions. Preliminary concentration of specimen fluids was achieved by ultrafiltration through collodion sacks. A preliminary wash of the oven-dried paper strips with 95 per cent ethanol was found essential to clear the paper of buffer salts and insure that the pH in the oxidation procedure remained in the 3.0-3.5 range. Close control of the reagent composition and timing of each step were found necessary. Inclusion of 40 per cent ethanol in the oxidation bath and immersion of dry strips were required to insure rapid penetration of the periodic acid. Control of the oxidation procedure at 20 ± 0.5° for 12 minutes was of prime necessity to maintain a low background color. Also, the concentrations of hydrochloric acid in the dye bath and in the wash solutions were found to affect the quality of the final stain. The ethanol wash served to remove residual sulfite and hydrochloric acid and stabilize the color. The new method has been applied to the analysis of several body fluids of normal persons and patients with certain disease entities, and satisfactory glycoprotein distribution patterns have been obtained.