Antioxidant Activity of Dopamine-Modified Hydrogels Containing Cross-linked Hyaluronic Acid

Abstract

Purpose : : In this study, we made dopamine-functionalized hydrogels containing a cross-linked hyaluronic acid (HA) network and investigated their antioxidant activities.Methods : In the first step, we made poly hydroxyethyl methacrylate(p(HEMA))-based hydrogels post-modified with an interpenetrating polymer network(IPN) structure composed of HA polymers and a p(HEMA) network. The subsequent functionalization with dopamine via an amide coupling reaction resulted in the antioxidant hydrogels. Their antioxidant activities were evaluated using 2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) and 2,2-diphenyl-1-picrylhydrazyl radical scavenging assays.Results : The dopamine-modified hydrogels exhibited significant antioxidant activities, when compared to unmodified control. The presence of the HA–IPN structure improved the surface wettability of the hydrogel while dopamine-conjugated IPN hydrogel did not demonstrate the significant difference compared to hydrogel control. Dopamine-modified hydrogels exhibited high transmittance (>88%).Conclusion : The results demonstrate that the development of antioxidant hydrogels based on dopamine-conjugated HA–IPN structures may help develop ophthalmic and biomedical materials.