Chitosan-Based Double Network Hydrogel with Strong Adhesion and ROS Scavenging for Accelerating Wound Healing

Hydrogel is increasingly appreciated as a reliable dressing for wound repair and regeneration due to the established favorable microenvironment for healing. Thus, hydrogel with multiple synergistic functions are of particular interest in biomedicine. Herein, we develop a double network hydrogel with low swelling property, outstanding adhesive capacity, good biocompatibility, excellent anti-bacterial and ROS scavenging capacity, which shows potential for accelerating wound healing. Quaternized chitosan serves as the first network to endow the hydrogel with anti-bacterial capacity (75.18% for E. coli and 93% for S. aureus ). Zwitterionic monomer is copolymerized with acrylic acid to form the second network, which improves the mechanical properties and reduces the swelling behavior (ultralow swelling ratio of 2.42%). Tannic acid and dihydrocaffeic acid contribute excellent tissue adhesion (adhesion strengths of 124.4 kPa to pig skin) and antioxidant capacity (ROS scavenging rate of 96%). Based on these advantages, the hydrogel greatly facilitates the wound closure, as well as promotes epithelialization, collagen deposition and neovascularization.