Accelerating the excisional wound closure by using the patterned microstructural nanofibrous mats/gentamicin-loaded hydrogel composite scaffold

Ideal artificial tissue scaffolds should provide an in vitro microenvironment comparable to native human skin tissue to direct cell functions, regulate tissue homeostasis, and promote tissue regeneration. A sandwich-like composite scaffold consisting of a hydrogel layer and two aligned nanofibre layers was fabricated and applied as a wound-healing dressing. Gentamicin was preloaded into the hydrogel middle layer and naturally released for antibacterial activity during the healing period. Nanofibrous layers embedded on the top and bottom surfaces of the hydrogel improved the tensile strength fivefold (1560 kPa and 465% strain) while serving as a diffusion barrier to reduce the gentamicin initial burst release (30%-15%). Inspired by the extracellular matrix (ECM), the surface of nanofibre top layer was patterned with triangular microarrays using micro-moulding approach to reflect the multidimensional structure of ECM. Biocompatibility of the scaffold is proven from cytotoxicity and haemolysis studies. Fibroblast cells revealed a highly elongated and consistent alignment modulated by the micropatterned fibrous layer and directed their migration towards the wound area. Excisional wounds treated with the scaffold promoted 97.49% wound closure with low inflammation and rapid re-epithelialization and angiogenesis. This scaffold, with its tailored functionality capable of accelerating wound healing, has high po-tential in tissue engineering applications.

Automated summary

This study fabricated an artificial tissue scaffold that mimics the microenvironment of native human skin tissue, showing potential for directing cell functions and promoting tissue regeneration. The scaffold consisted of a hydrogel layer and nanofibre layers, with preloaded antibacterial agents. The scaffold exhibited improved mechanical strength and controlled release of antibacterial agents. In vitro studies demonstrated biocompatibility and cell migration towards the wound area. In vivo experiments showed accelerated wound healing with low inflammation and rapid re-epithelialization and angiogenesis.