Polyphenol-mediated chitosan/polyvinyl alcohol hydrogel reinforced by graphene oxide for antibacterial and antioxidative wound dressing

Traditional hydrogels are limited by their loose three-dimensional network structure, inadequate mechanical strength, and insufficient synergistic antibacterial and antioxidant activities, which restrict their application as high-performance wound dressings. In this study, a graphene oxide (GO)-reinforced ternary composite hydrogel wound dressing (PVA/CS-GA/GO) based on polyphenol-modified chitosan and polyvinyl alcohol was successfully fabricated via a green repeated freeze–thaw process. The effects of GO incorporation on the microstructure, mechanical properties, antibacterial activity, and antioxidant performance of the composite hydrogels were systematically investigated. The results demonstrated that, at the optimal GO content, the composite hydrogel exhibited a tensile strength of 9.3 kPa and an elongation at break of 2163.7%, representing approximately 1.2-fold and 1.3-fold increases, respectively, compared with the PVA/CS-GA hydrogel. Moreover, GO incorporation further enhanced the antibacterial and antioxidant performances of the hydrogel, achieving a maximum antibacterial rate of 99.8% against Escherichia coli ( E.coli ) and increasing the DPPH radical scavenging activity to 94.8%, corresponding to an approximately 1.9-fold improvement over the PVA/CS-GA hydrogel. In addition, the composite hydrogel exhibited excellent structural stability and biocompatibility, simultaneously achieving mechanical reinforcement and multifunctional performance enhancement. These findings provide a theoretical basis for the design and development of high-performance multifunctional hydrogel wound dressings.