Near-infrared radiation of gold–platinum submicron particle-decorated nonwoven mats enhances wound healing: In vitro and In vivo studies

Abstract

Because of their biocompatibility and unique optical and electrical properties, Pt nanoparticles (NPs) have been extensively utilized in biomedical applications. However, the use of pure Pt NPs is hindered by the high costs of raw material and absorption at ultraviolet wavelengths. To leverage the benefits of Pt particles while mitigating their drawbacks, we applied electrospinning technology to prepare polyacrylonitrile (PAN) nonwoven mats decorated with gold and platinum submicron particles (Au5Pt3 submicron particle-decorated PAN). We examined the surface morphology, elemental composition, and chemical structure of the resultant Au5Pt3-decorated PAN nonwoven mats by field emission scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, and EDX elemental mapping. When subjected to near-infrared (NIR) illumination, the Au5Pt3-decorated PAN nonwoven mats showed a more stable temperature rise than pure PAN nonwoven mats or Au PAN nonwoven mats. Inductively coupled plasma spectrometry demonstrated that the Au5Pt3-decorated PAN nonwoven mats can release more Pt ions under NIR illumination, reaching concentrations of up to approximately 8 ppm. The Au5Pt3-decorated PAN nonwoven mats exerted positive effects in a wounded mouse model, with or without NIR irradiation: the films did not cause wound adhesion or fibrosis, and excellent skin tissue healing and collagen regeneration were observed. Moreover, when combined with NIR illumination, the Au5Pt3 submicron particle-decorated PAN nonwoven mats more strongly inhibited the growth of Gram-positive and Gram-negative bacteria and more strongly enhanced blood vessel generation, compared with the same mats in the absence of NIR illumination. Regardless of NIR irradiation, the Au5Pt3 submicron particle-decorated PAN nonwoven mats do not show significant damage to the liver or kidney in mice. Overall, treatment with these Au5Pt3 submicron particle-decorated PAN nonwoven mats does not result in toxicity in mice and exerts a positive effect on wound healing when combined with NIR irradiation, with enhanced angiogenesis and collagen regeneration.