CuS nanotube/chitin composite hydrogel with enhanced photothermal efficiency for near-infrared-activated bacteria-killing

Abstract

The research on biocompatible materials which exhibit remarkable antibacterial capability has always attracted lots of interests. Among numerous antibacterial materials, CuS micro-/nanomaterial has gained attention as a promising option due to its low toxicity and efficiently photothermal effect. In this study, CuS nanotube/chitin composite hydrogel was prepared by crosslinking with chitin. Due to the prominent photothermal conversion efficiency of CuS nanotube which was up to 64.3 %, the as-prepared composite hydrogel showed enhanced photothermal effect under near-infrared (NIR) illumination. The composite hydrogel also showed a typical peroxidase-like activity which can convert H2O2 into an extremely oxidative and toxic hydroxyl radicals (•OH). The prominent photothermal effect and peroxidase-like activity made the composite hydrogel perform well in antibacterial against Escherichia coli with NIR activation. The possible mechanism of NIR-activated antibacterial from CuS nanotube/chitin composite hydrogel was discussed as well. The results of this work indicate that the CuS/chitin composite hydrogel with enhanced photothermal effect could be a new NIR-activated antibacterial agent used for sterilization.