Concentration of sodium hyaluronate in serum

A radioassay for sodium hyaluronate using high-affinity binding protein from bovine cartilage has been modified for serum analysis. The accuracy of the method was checked by isotope dilution experiments and by recovery studies with exogenous hyaluronate. The between-assay standard deviation in the determination is 15-20%. The concentration of sodium hyaluronate in healthy adults (blood donors) is in the range of 10 to 100 micrograms/l with a mean value in the order of 30 to 40 micrograms/l. This is a lower concentration than previously reported. The same level was found in young people. Higher hyaluronate concentrations were noted in persons above 50 years of age. Analysis of plasma showed a slightly higher average hyaluronate level (5%) than in serum from the same persons. There were no notable sex differences. Analysis of serum and plasma from adult animals (rat, rabbit, dog, pig, goat, sheep, cow and horse) gave hyaluronate concentrations of the same order or higher than in human serum.