INFLUENCE OF THE IONIC-STRENGTH ON THE DIMENSIONS OF SODIUM HYALURONATE

In this paper, we present some results on the dimensions-radius of gyration [rho2]1/2 and persistence length L(p)-and the intrinsic viscosity [eta] of different molecular weights of hyaluronate samples using light scattering and viscosity experiments. Particular attention has been given to the salt concentration effects. Extension of Odijk's model and application of the Yamakawa-Fujii theory lead to a good description of electrostatic expansion of the molecule assumed as a wormlike chain. A good agreement has been found between calculated and experimental values and allows the determination of the intrinsic persistence length L(p) is-congruent-to 80 angstrom. In addition, the Mark-Houwink exponent a(eta) relating intrinsic viscosity with molecular weight and its dependence with ionic strength is predicted. A good agreement between calculated and experimental data is found, and the usually high value of a(eta) measured on this polymer is confirmed and justified.