Hydrogel/nanofibrous membrane composites with enhanced water retention, stretchability and self-healing capability for wound healing

Hydrogel has emerged as one of the most promising dressings for wound healing owing to the creation of moist environment. However, it suffers from poor water retention capability and weak mechanical property. Therefore, development of dressings with durable moisture retention, robust mechanical property, and self-healing performance is urgently needed in practical applications. Herein, we developed a bilayered composite dressing consisting of breathable and hydrophobic polyurethane/polydimethylsiloxane (PU/PDMS) nanofibrous membrane and double-crosslinked chitosan-based hydrogel with dynamic Schiff base bonds and non-dynamic photo-crosslinking bonds. Combined with the nanofibrous membrane as protection and mechanical support, the bilayered hydrogel composites presented enhanced water retention capability to provide sustained moist environment, excellent stretchable and compressive performance to bear deformation, fast self-healing and good cyclic resilience to endure frequent movements. The in vivo study indicated their effective therapeutic effect in a rat model with full-thickness skin wounds. This study demonstrated that the hydrogel/nanofibrous membrane composite represented a promising candidate as dressing material for wound healing.