A bi-layered scaffold of a poly(lactic-co-glycolic acid) nanofiber mat and an alginate–gelatin hydrogel for wound healing

A resveratrol-loaded bi-layered scaffold (RBS) that consists of a resveratrol-loaded poly(lactic-co-glycolic acid) (Res-PLGA) electrospinning nanofiber mat (upper layer) and an alginate di-aldehyde (ADA)-gelatin (GEL) crosslinking hydrogel (ADA-GEL) (lower layer) was fabricated as a wound dressing material. It was made through mimicking the epidermis and dermis of the skin. The RBS exhibited good hemostatic ability and proper swelling ability. Furthermore, HaCaT cells and human embryonic skin fibroblasts (ESFs) were also cultured in the nanofiber layer and hydrogel layer of RBS, and the results indicated that both HaCaT and ESFs could grow well in the materials. The in vivo experiment using a Sprague-Dawley (SD) rat skin wound as a model showed that the RBS could accelerate the wound healing rate compared with the Res-PLGA group and ADA4-GEL6 group. These results indicated that this resveratrol-loaded bi-layered scaffold can be a potential candidate in promoting wound healing.