[Interaction of collagen with sodium ions]

A change was found in the correlation between donor and acceptor adsorptive sites on the collagen surface in NaCl solution treatment. The number of binding sites was estimated by the value of spin-spin interaction constant (alpha) of native and treated by 3% NaCl solution; it accounts for 12,5 sites per 100 amino acid residues. A non-specific effect of water freezing after Na+ and K+ ions penetration was noticed.