A synergistically antimicrobial and antioxidant hyaluronic acid hydrogel for infected wounds

Bacterial infections during wound healing impede the healing process and trigger local or systemic inflammatory reactions. Consequently, there is an urgent need to develop a new material with antimicrobial and antioxidant properties to promote infected wound healing. A synergistically antimicrobial and antioxidant hyaluronic acid hydrogel (HMn) is prepared by employing MnO₂ nanosheets into 4ARM-PEG5000-SH crosslinked methacrylated hyaluronic acid (HAMA) network. The coordination between sulfhydryl groups of 4ARM-PEG5000-SH and MnO₂ nanosheets ensures entrapment of the nanosheets within the hydrogel, while the interaction between 4ARM-PEG5000-SH and HAMA results in facile gelation through thiol-ene click reaction. MnO₂ nanosheets exhibit strong photothermal properties and reactive oxygen species (ROS) scavenging abilities, while hyaluronic acid promotes wound healing. When subjected to near-infrared (NIR) irradiation, the HMn achieves a bactericidal rate of 95.24 % for Staphylococcus aureus and nearly 100 % for Escherichia coli. In animal experiments, treatment with the HMn under NIR irradiation results in the best wound healing outcomes. Both in vitro and vivo biocompatible assays demonstrate that the HMn has rarely cell cytotoxicity and tissue damage. The HMn is easy to prepare and has good biocompatibility as well as efficient antibacterial and antioxidant properties, providing a novel method for the treatment of infected wounds.