Potential Multi-Functional Sprayable Poly(N-Isopropylacrylamide)/Dextran Hydrogel Dressings With Incorporation of Silver Nanowires

Abstract

Smart polymer-based hydrogels with properties such as temperature-responsive performance, sprayability, antimicrobial effects, and antioxidant activity hold promise for wound dressing applications. In this study, aminated poly(N-isopropylacrylamide) (PNIPAM-NH₂) was synthesized via the free radical polymerization of N-isopropylacrylamide (NIPAM), and dopamine-grafted aldehyde dextran (Odex-DA) was also prepared. A pre-solution was then prepared by combining PNIPAM-NH₂, Odex-DA, and silver nanowires (AgNWs) at room temperature conditions with its temperature-responsive behaviour demonstrated by injecting the pre-solution into the water at a temperature of 37°C leading to the transition of the OPAg pre-solution to hydrogels. The obtained multi-functional OPAg hydrogels exhibited an interconnected microstructure and injectability. In addition, the OPAg pre-solution displayed sprayability, forming an adherent hydrogel layer on human skin upon application. Furthermore, the OPAg hydrogels exhibited strong antimicrobial ability against E. coli and S. aureus, along with favourable DPPH scavenging ability. Cytocompatibility was confirmed by CCK-8 assays and fluorescence imaging with NIH-3T3 cells. Overall, this study developed a multifunctional, sprayable hydrogel with strong potential for use in wound healing.