C-13 NMR INVESTIGATION OF SYNOVIAL-FLUIDS

C-13 NMR spectra of synovial fluids from 20 patients suffering from rh eumatic diseases have been recorded. Structural changes in hyaluronic acid, the main carrier of the viscoelastic properties of synovial flui d, could be observed in the NMR spectra of the native biological fluid . By comparing these spectra with those of purified hyaluronic acid, a rough estimation of the degree of depolymerization of synovial hyalur onic acid was possible. The patients with rheumatoid arthritis appeare d to have a lower degree of polymerization compared to patients with o steoarthrosis. Thus, C-13 NMR spectroscopy provides useful information about biophysical properties of synovial fluid.