Engineered, Radially Aligned, Gradient-Metformin-Eluting Nanofiber Dressings Accelerate Burn-Wound Healing

Introduction: Deep, second-and third-degree burn injuries may lead to irreversible damage to the traumatized tissue and to coagulation or thrombosis of the microvessels, further compromising wound healing. Engineered, morphologically gradient drug-eluting nanofiber dressings promote wound healing by mimicking tissue structure and providing sustained drug delivery, which is particularly beneficial for wound management. Methods: This study exploited a resorbable, radially aligned nanofiber dressing that provides the sustained gradient release of metformin at the wound site using a pin-ring electrospinning technique and a differential membrane-thickness approach. Results: The experimental results suggested that the electrospun nanofibrous dressings exhibited uniform and radially oriented fiber distributions. In vitro, these dressings offered an extended release of metformin for 30 d. The incorporation of water-soluble metformin significantly enhanced the hydrophilicity of the nanofiber membranes. Moreover, the in vivo burn-wound-healing model of rats showed that the radially aligned gradient metformin-eluting poly(lactic-co-glycolic acid) (PLGA) nanofibers exhibited significantly superior healing capability compared to the pristine PLGA, metformin-eluting, and control dressings. Histological images showed that the mesh/nanofibers produced no adverse effects. Conclusion: The findings in this study emphasize the potential of resorbable, radially aligned nanofiber dressings as advanced wound care solutions, offering broad applicability and meaningful clinical impact.