Preparation of ″Five-in-One″ Chitosan Hydrogel for Infectious Wound Repair

Following damage to the skin and mucous membranes, bacterial infections, and excessive oxidative stress often lead to inflammatory responses and impaired wound healing, which can even be life-threatening. Surgical dressing combined with antimicrobial agent use is the major therapy. However, traditional gauze dressings are prone to causing secondary injuries, while systemic antibiotic therapy often fails to deliver sufficient drug concentrations at the wound site and carries the risk of systemic toxic side effects. Hydrogel dressing is a hot research field because of its breathability, biocompatibility, and easy access for modification. The healing of infected wounds is a complex process during which tough adhesion of the dressing to the wound and effective elimination of inflammation are both important for successful wound healing. To achieve this goal, we designed a "five-in-one" hydrogel wound dressing, CS/TA, using natural components including chitosan and tannic acid. Briefly, the CS/TA dressing was simultaneously characterized by five important capabilities, including tissue adhesion, self-healing property, extensibility, and antibacterial and antioxidant properties. The excellent adhesiveness, self-healing ability, and extensibility allowed the CS/TA dressing to conform to dynamic tissue changes and adhere closely to the wound. Moreover, the CS/TA dressing effectively eliminated bacteria and scavenged excess free radicals, thereby minimizing tissue inflammation. As a result, significantly accelerated wound healing was achieved in an infected wound model. To conclude, the study provided a novel perspective on hydrogel dressing design, and the five-in-one CS/TA dressing demonstrated great potential for infected wound treatment.