Janus Intelligent Antibacterial Hydrogel Dressings for Chronic Wound Healing in Diabetes

Long-term recurrent infections are one of the significant reasons why chronic diabetic wounds are difficult to heal, and the treatment of chronic wounds remains a major clinical challenge. In this work, we developed a kind of Janus hydrogel dressing capable of adjusting the complex microenvironment of wounds for promoting the healing of diabetic chronic wounds. The Janus hydrogel dressings are made of zwitterionic polymers and gentamicin sulfate-modified hyaluronic acid (HA-GS). One side of the hydrogel dressings was brushed with chitosan to act as a bridge between wound dressings and wound tissues. Thus, the wound dressings showed Janus properties with an antifouling surface on one side and an adhesive surface on the other, where the antifouling surface of zwitterionic hydrogels can avoid the adhesion of external bacteria, while the adhesive surface helps the dressings to be fixed on the wound. Moreover, the antibiotic GS was connected to HA through Schiff's base, and thus it can be intelligently released in response to the acidic environment of infected wounds to kill the internal bacteria. The Janus hydrogel dressings were carefully characterized and investigated. In vivo results of a diabetic rat infected wound model showed that the Janus hydrogel dressings could effectively inhibit inflammation, accelerate the formation of granulation tissues and collagen deposition, and promote wound healing. Therefore, this multifunctional hydrogel dressing is a promising candidate for chronic wound healing in clinical practice.