Protocatechuic acid grafted chitosan/oxidized glucomannan hydrogel with antimicrobial and anti-inflammatory effects for enhancing wound repair

Oxidative stress, inflammation, and bacterial infection are critical barriers to wound healing. In this work, a composite wound dressing was designed to promote wound healing and reduce complications. A hydrogel with antibacterial, anti-inflammatory, and antioxidant properties was prepared by crosslinking chitosan (CS) and oxidized konjac glucomannan with Mg²⁺. We named the prepared hydrogel CPO/Mg²⁺. The proposed hydrogel demonstrated a significant capacity for promoting wound healing. Experimental results indicate that the CPO/Mg²⁺ composite hydrogel exhibits a bacteriostatic rate of over 95 % against S. aureus and P. aeruginosa. Furthermore, CPO/Mg²⁺ reduced oxidative damage to L929 cells in an H₂O₂-induced ROS microenvironment and promoted the polarization of macrophage M2. In vivo full-thickness skin defect experiments revealed that the CPO/Mg²⁺ composite hydrogel enhances collagen deposition and angiogenesis, achieving a closure rate of over 95 % for infected wounds within 14 days. This novel composite hydrogel offers an effective strategy for the repair of infected wounds.