QUANTIFICATION AND CHARACTERIZATION OF GLYCOSAMINOGLYCANS AT THE NANOGRAM LEVEL BY A COMBINED AZURE-A SILVER STAINING IN AGAROSE GELS

A rapid, sensitive, and nonradioactive method has been developed for t he quantification and characterization of glycosaminoglycans. The meth od is based on the separation of different types of glycosaminoglycans in agarose gel and subsequent fixation and staining with the cationic dye azure A, followed by silver enhancement. Densitometric analysis o f the silver deposition gives a linear response between 1 and 20 ng fo r chondroitin and dermatan sulfate and between 2 and 40 ng for heparan sulfate. The detection limit is about 250 pg. The staining procedure was applied for the quantification and characterization of glycosamino glycans in human serum, urine, and lung and in mouse kidney glomeruli. It requires only 10 mu l serum, 2 mu l urine, and only a single cryos ection in case of tissue. The method is at least as sensitive as stain ing with radioactive markers and about 200 times more sensitive than c onventional glycosaminoglycan-staining methods. (C) 1994 Academic Pres s,Inc.