[Study of different proteoglycan salts].

The authors have devised the methods for preparing free hyaluronic acid (HA) and non-aggregating fraction of protein-chondroitin-keratan sulfate (PCKS), as well as those for preparing their Na+, K+, Ca2+ and Mg2+ salts (acid and neutral). Infrared spectroscopy has demonstrated the presence of intermolecular hydrogen bonds, formed by hydroxyl groups, in HA and PCKS macrocomplexes and in PCKS acid salts. HA salts appeared not to form macrocomplexes at the expense of intermolecular hydrogen bonds.