ENTHALPY OF MIXING GLYCOSAMINOGLYCANS WITH AQUEOUS NACL

Calorimetric measurements of ΔH, the enthalpy of mixing with NaCl solutions per mole of polymer charge equivalent, have been made for the sodium salts of hyaluronate, chondroitin 4‐sulfate, and chondroitin over the range msf = 0–0.5 (where msf is final NaCl molality); corrections were made for the enthalpy of dilution of NaCl. Values of ΔH for the range msf = 0–0.1 agree reasonably well with a theoretical estimate from the infinite line charge theory of polyelectrolytes. In order to apply the latter, calculations of several average short‐range atomic spacings in hyaluronate were made from a statistical model with use of energy parameters which provide a good fit to experimental values of unperturbed dimensions. Copyright © 1979 John Wiley & Sons, Inc.