Structural Modifications and Solution Behavior of Hyaluronic Acid Degraded with High pH and Temperature.

Hyaluronic acid (HA) is a macromolecule with valuable benefits over its range of molar masses (MM). Degradation studies are relevant to maintain the same purity level in biomedical studies when using HA of different MM. We degraded HA via high pH and temperature and evaluated its MM, solution behavior, and structure over time. After 24 h, low MM HA was predominant, and the MM decreased from 753 to 36.2 kDa. Dynamic light scattering (DLS) showed a decrease in the number of HA populations, and the solution tended to be less polydispersed. The zeta potential varied from - 10 to - 30 mV, close to the stable range. FTIR showed that the primary structure of HA was affected after only 48 h of reaction. These results are relevant for the production of low MM HA to be used or mixed with high MM HA, generating structured biomaterials for biomedical applications.