An injectable photocuring silk fibroin-based hydrogel for constructing an antioxidant microenvironment for skin repair.

Skin has a protein microenvironment dominated by functional collagen fibers, while oxidative stress caused by injury can greatly slow down the progress of wound healing. Here, methacrylated dopamine was incorporated into methacrylated silk fibroin molecule chains to develop an injectable hydrogel with photocuring properties for constructing an antioxidant skin protein microenvironment. This silk fibroin-based hydrogel (SF- g -SDA) showed good tensile and adhesion properties for adapting to the wound shape and skin movement, exhibited stable mechanical properties, good biodegradability and cytocompatibility, and promoted cell adhesion and vascularization in vitro . In addition, its phenolic hydroxyl-mediated antioxidant properties effectively protected cells from damage caused by oxidative stress and supported normal cellular life activities. In animal experiments, SF- g -SDA achieved better skin repair effects in comparison to commercial Tegaderm™ in vivo , showing its ability to accelerate wound healing, improve collagen deposition and alignment in newly fabricated tissues, and promote neovascularization and hair follicle formation. These experimental results indicated that the SF- g -SDA hydrogel is a promising wound dressing.