By M. L. Bernuzzi, Fedegari Group and A. Giori, IBSA Farmaceutici
Several reports on degradation of HA involving microwaves, UV or γ-rays have been published. Rheological studies also show that HA solutions degrade at high temperature: viscosity of the solutions decreases in time as a function of temperature. Therefore, the thermal sterilization treatment of HA solutions represents a great challenge. An optimized moist-heat sterilization cycle can minimize product degradation (and change of molecular weight) maintaining the required viscosity for the specific application.