Quantitative microanalysis of aortic glycosaminoglycans

Abstract

Glycosaminoglycans (GAGs) are isolated from approximately 250 mg of aortic tissue by enzymatic degradation of tissue, followed by potassium acetate precipitation of GAGs. Hyaluronic acid, heparitin sulfate, and dermatan sulfate are quantitated by densitometric scanning of cellulose acetate electrophoretograms. Chondroitin 4-sulfate and chondroitin 6-sulfate are quantitated in separate aliquots of the aortic extract by the Morgan-Elson determination of N-acetyl hexosamines, following selective enzymatic digestions of the chondroitin sulfate isomers. In both analyses, absolute amounts of GAGs are determined by comparison with standard curves prepared simultaneously. The accuracy for this micromethod was ±0.03–±0.07 μg at the 99% confidence level for determination of the five individual GAGs in mixtures of GAGs whereas the precision was ±0.03–±0.09 μg at the 99% confidence level over the range of 2.5–50.0 μg of GAG.