3D/2D TMSs/TiO2 nanofibers heterojunctions for photodynamic-photothermal and oxidase-like synergistic antibacterial therapy co-driven by VIS and NIR biowindows

With the increasingly serious problem of antimicrobial resistance and the lack of clinical response strategies, the development of new antibacterial materials is imminent. Herein, a VIS/NIR co-irradiation photodynamic-photothermal and oxidase-like synergistic antibacterial platform of transition metal sulfide/TiO2 nanofibers (TMSs/TiO2 NFs) is proposed to fight bacterial infection. On one hand, three-dimensional (3D) MoS2 nanoflowers load can quickly capture the photogenerated electrons of two-dimensional (2D) TiO2 nanofibers, inhibit the recombination of electron-hole pairs and greatly increase the yield of reactive oxygen species (ROS), thereby overcoming the UV sterilization defects of pure TiO2, endowing TiO2 excellent photodynamic antibacterial ability in the long-wavelength region. On other hand, with the combination of MoS2 and TiO2, the photothermal effect of the 3D/2D heterostructure (MoS2/TiO2 NFs) was significantly enhanced and the local temperature rose to above 50 °C in a short time, which was enough to induce the inactivation of bacterial protein, thereby providing an efficient secondary sterilization effect. In addition, MoS2/TiO2 NFs has fascinating oxidase-like activity, which further accelerated the oxidation of physiologically relevant antioxidants in bacteria. In the end, MoS2/TiO2 NFs exerted outstanding antibacterial efficiencies against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) through the synergy of photodynamic-photothermal and oxidase-like performance. Meanwhile, MoS2/TiO2 NFs antibacterial platform effectively accelerated the healing of S. aureus-infected wounds and showed negligible toxicity and hemolysis on normal cells and tissues. Hence, this study contributed an effective alternative strategy for reducing the use of antibiotics, providing new ideas for application of semiconductor nanomaterials in collaborative combination therapy.