Surface modification of sodium hyaluronate with ferulic acid to enhance its application performance

Abstract Hyaluronic acid (HA) is a mucopolysaccharide alternately linked by glucuronic acid and n ‐acetylglucosamine, which is usually used as a moisturizer in cosmetics. In this study, HA derivative (FA‐HA) was prepared by modifying sodium hyaluronate with ferulic acid (FA). The chemical and morphological structure of FA‐HA were characterized by UV, FTIR, 1 H‐NMR, DLS and TEM. The results showed that FA was grafted onto HA chains via ester bonds and self‐assembled into nanoparticles in aqueous solution. The introduction of FA endowed the nanoparticles with antioxidant function. The FRAP value of 10 mg/mL FA‐HA was 1.985 mM, and the clearance rate of O 2 − , DPPH + and ABTS + could reach 83.13%, 88.86% and 99.48% respectively. Moreover, FA‐HA can be used as Pickering emulsifiers to stabilize the emulsion. The results showed that the size of emulsion droplets decreased as the concentration of FA‐HA increased. When the mass ratio of oil to water was 7/3, the emulsion droplets were the smallest. The addition of sodium chloride will increase the size of emulsion droplets, destroying the stability of the emulsion. In addition, FA‐HA was also universal and was capable of emulsifying alkanes, esters, and natural oils, which was expected to be applied in the cosmetics and food fields.