Engineering a skin-mimicking asymmetric poly(L-lactic acid)/gelatin bioscaffold for skin repair

This study developed a biomimetic asymmetric nanofibrous scaffold combining poly(L-lactic acid) (PLA) and gelatin to replicate layered epidermal–dermal architecture for enhanced skin repair. Using sequential and coaxial electrospinning, the team fabricated PLA top layers for barrier protection and gelatin-based porous bottom layers to promote hydration and cellular infiltration. Genipin crosslinking stabilized the gelatin layer and significantly enhanced scaffold mechanics, as confirmed by FTIR and TGA analyses. Structural evaluation (SEM and TEM) revealed uniform fiber morphology, defined core–shell organization, and increased nanofiber diameter after crosslinking. Mechanical characterization demonstrated that the PG(CL) membrane achieved tensile strength (3.60 ± 0.39 MPa), stiffness (103.65 ± 2.68 MPa), and controlled extensibility appropriate for skin-mimetic applications. Hydration/degradation studies showed bounded swelling and improved stability relative to non-crosslinked membranes. In vitro assays with NIH-3T3 fibroblasts confirmed high viability, enhanced proliferation, and superior wound closure (95% scratch closure at 48 h). Overall, the genipin-stabilized PG(CL) scaffold integrates structural, mechanical, and biological functionality suitable for next-generation wound dressings.