Visible-Light-Driven Photocatalysis-Enhanced Nanozyme of TiO2 Nanotubes@MoS2 Nanoflowers for Efficient Wound Healing Infected with Multidrug-Resistant Bacteria.

Abstract

To enhance the catalytic activity of the nanozymes for efficient wound healing infected with multidrug-resistant bacteria, photo-based motivations have been suggested, but attention is mainly focused on the external stimulus of near-infrared light, while the inexhaustible visible one is promising but lack of study. Herein, an efficient visible light-stimulated peroxidase-like nanozyme system, TiO2 nanotubes coated with MoS2 nanoflowers (TiO2 NTs@MoS2 ), is discovered for efficient bacterial treatment. Based on the synergetic effects between the two components, the bandgap of the TiO2 NTs can be narrowed from 3.2 to 2.97eV due to the MoS2 loading, which extended the light response of TiO2 to visible-light range and enhanced the photocatalyticactivity accordingly. Meanwhile, the peroxidase-like activity of MoS2 can be significantly enhanced due to the combination with TiO2 NTs in return. Especially, the peroxidase-like activity of the TiO2 NTs@MoS2 nanocomposite can be further improved under the sunlight irradiation, rendering much more hydroxyl radical (•OH) generation. Accordingly, the as-obtained TiO2 NTs@MoS2 shows an outstanding antibacterial effect against drug-resistance extended spectrum β-lactamases producing Escherichia coli and methicillin-resistant Staphylococcus aureus under the visible light. In vivo wound healing test further confirms the high antimicrobial efficiency and good biocompatibility of the synergistic antimicrobial system.