The isolation and characterization of glycosaminoglycans in normal human serum

The optimization of conditions for the isolation and characterization of human serum glycosaminoglycans (GAG) is described, together with studies of the accuracy and reproducibility of the method. The principle of the method is proteolytic digestion of serum using papain followed by precipitation of GAGs from the digested sample with cetyl pyridinium chloride (CPC). The uronic acid level and electrophoretic separations can be obtained from a 5 ml serum sample. The mean CPC-precipitable uronic acid level in pooled normal serum was 10.8 mg l(-1) serum. Using enzymatic and chemical analysis the major serum GAG was shown to be chondroitin sulphate (CS). Two distinct electrophoretic fractions were identified both consisting of CS but differing in their degree of sulphation. Dermatan sulphate, heparan sulphate and hyaluronic acid were not detected.