[Infrared spectra of certain proteoglycans].

IR spectra of high-purified potassium salts of hyaluronic acid (HA), non-aggregation fraction of protein-chondroitin-keratan sulfate (PChKS) and heparin fractions containing 3 (H-3) and 4 (H-4) residues of sulfuric acid per dimer of polymer have been measured. An absorption band of 1150 cm-1 has been observed in the spectra of both HA and PChKS but has not been found in the spectra of H-3 and H-4. Observation of this band in the spectra of some heparin preparations indicates that they contain the admixtures of HA, PChKS and other proteoglycans. A previously suggested method for isolation of heparin fractions H-3 and H-4 makes it possible to obtain preparations that do not contain the admixtures of other proteoglycans.