Near-infrared light-triggered silk fibroin hydrogels integrated with polydopamine-modified nanoparticles for enhanced wound healing and infection control

Abstract

This study presents the development and evaluation of a novel silk fibroin (SF)-based hydrogel composite, SiPDA/Ag-C, enhanced with polydopamine (PDA)-modified silver nanoparticles (Ag@PDA) and PDA-modified curcumin (Cur-PDA), for skin wounds treatment and infection control. Dopamine readily oxidizes and reacts with SF to form hydrogels. By in-situ synthesizing silver nanoparticles (Ag NPs) on the surface of PDA nanospheres, Ag@PDA achieves a dual antibacterial effect. It combines the photothermal antibacterial property of PDA with the ability of Ag NPs to disrupt bacterial membranes and DNA. Coating PDA on the surface of curcumin creates Cur-PDA nanoparticles, which not only enhance curcumin's bioavailability but also integrate curcumin's anti-inflammatory and antioxidant properties with PDA's antioxidant and photothermal antibacterial capabilities. Combining Ag@PDA and Cur-PDA into the SF hydrogel matrix results in the SiPDA/Ag-C hydrogel. The hydrogel leverages the photothermal properties of PDA to achieve non-invasive wound healing under near-infrared (NIR) light irradiation. The SiPDA/Ag-C hydrogel could significantly inhibit the growth of Staphylococcus aureus and Escherichia coli in vitro and in vivo, and promote wound healing by reducing inflammation, enhancing antioxidant capacity, and stimulating tissue regeneration. In vivo study shows that compare with the treatment of SiPDA/Ag-C hydrogel alone, the combined treatment with NIR irradiation could significantly inhibit bacterial growth and improve tissue repair. The hydrogel also exhibited excellent biocompatibility, biodegradability, and minimal cytotoxic effects, making it a promising candidate for advanced wound care and tissue engineering applications.