Chondroitin sulphate of calf knee-joint cartilage.

Chondroitin sulphate from different layers of calf knee-joint cartilage has been isolated and purified. Analysis for hexosamine, uronic acid, sulphate and relative proportions of the 4- and 6-isomers revealed no differences between the layers. However, an increase in the average molecular weight of the chondroitin sulphate was found to correspond with distance from the articular surface. In particular, the average molecular weight in the epiphyseal cartilage was significantly higher than that in the articular cartilage. The chondroitin sulphate of the 40-mu-mthick articular surface layer was found to have a higher molecular weight than the rest of the articular part of the cartilage and also to be more polydisperse. These results, regarding molecular size, are in agreement with the cetylpyridinium chloride cellulose microcolumn fractionation patterns.