Metal-Phenolic Network (MPN) Modified Janus Fibrous Hydrogel Scaffold for Infected Diabetic Wound Healing

Management of infected diabetic wounds with large amounts of biofluid is challenging to treat due to localized edema-induced ischemia. Traditional hydrophilic dressings retain wound exudate, raise bacterial infection, and hinder wound healing. Herein, a multifunctional double-layer Janus fibrous hydrogel with a hydrophobic and superhydrophilic potential was designed to accelerate the healing of infected diabetic wounds. The outer hydrophobic layer is composed of a poly(vinylidene fluoride)/cellulose acetate-based nanofibrous composite. In contrast, the inner superhydrophilic layer is composed of photo-cross-linked gelatin methacrylate/polycaprolactone based nanofibrous hydrogel coated with a zinc-dopamine-based metal-phenolic network complex. The bilayer Janus fibrous hydrogel was characterized for its structural, physicochemical, mechanical, swelling, antioxidant, antibacterial, and cytocompatibility properties. Results indicated that the outer hydrophobic layer possesses excellent antifouling self-cleaning potential and can prevent the entry of environmental microorganisms and moisture. On the other hand, the supramolecular complex coated inner layer possesses good antibacterial, antioxidant, and cell-supportive properties. Furthermore, the potential of Janus fibrous hydrogel for infected wound healing was evaluated by using infected diabetic BALB/c mice. The <i>in vivo</i> bacterial invasions and histological and immunological results indicated that the Janus fibrous hydrogel possesses good wound reconstruction potential, angiogenesis, and collagen deposition, making it appropriate for diabetic wound treatment.