Preparation, characterization and evaluation of a new film based on chitosan, arginine and gold nanoparticle derivatives for wound-healing efficacy.

It is well-known that the combination of polymers and nanoparticles (NPs) provides optimised wound dressing and accelerates wound healing. The knowledge about the structure and properties of these materials is of critical importance in biological processes related to wound healing. In this study, we prepared a chitosan (CS) film modified with arginine (Arg) and gold NPs (AuNPs) and investigated its effectiveness as a dressing material for wound healing. Fourier-transform infrared spectroscopy (FTIR) confirmed that Arg was successfully grafted on CS. The resultant CS-Arg/AuNP film was then characterised by transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The modification of Arg and AuNPs improved the hydrophilicity, mechanical strength and antibacterial properties of the film, which in turn provided an enhanced ideal environment for cell adhesion and proliferation. Cell Counting Kit-8 (CCK-8) was used to demonstrate the survival rate. Furthermore, the proteins involved in wound healing were evaluated qualitatively and quantitatively by immunofluorescence and western blotting, respectively. The skin defect models used for the in vivo studies revealed that the CS-Arg/AuNP dressing accelerated wound closure, re-epithelialization and collagen deposition. Our cumulative findings support the feasibility of using the proposed film as a promising candidate for tissue engineering of the skin in the near future.