Fabrication of hybrid photo-crosslinked hydrogels based on mercaptolated chitosan and methacrylated hyaluronic acid via thiol-Michael addition.

Impaired healing of chronic wounds typically stems from persistent oxidative stress, bacterial infection, and cellular dysfunction. Designing a multifunctional hydrogel dressing capable of adhesion, antioxidant activity, antibacterial ability, and cytocompatibility has demonstrated potential in wound healing applications. In this study, HTP composite hydrogels were fabricated based on thiolated chitosan (TCS) and methacrylated hyaluronic acid (HAMA) by incorporating polyethylene glycol diacrylate (PEGDA) and gelatin via the synergistic crosslinking of thiol-Michael addition and free-radical photopolymerization. Comprehensive characterization revealed that the hydrogel possessed an interconnected porous microstructure, appropriate swelling properties, and controllable degradation profiles, accompanied by pronounced shear-thinning behavior and tissue-adhesive capabilities. The obtained hydrogels demonstrated significant antibacterial activity against Staphylococcus aureus and Escherichia coli. Furthermore, the HTP hydrogels exhibited remarkable antioxidant capacity, scavenging DPPH and ABTS radicals. Additionally, the intracellular reactive oxygen species (ROS) scavenging ability was validated using NIH-3 T3 cells. Hemolysis assays and cytocompatibility evaluations confirmed the favorable hemocompatibility of the HTP hydrogels, which significantly promoted fibroblast proliferation and migration, indicating their substantial potential for wound healing applications.