NIR-Ⅱ window Triple-mode antibacterial Nanoplatform: Cationic Copper sulfide nanoparticles combined vancomycin for synergistic bacteria eradication.

The widespread use of antibiotics leads to the increasing drug resistance of bacteria and poses a threat to human health. Therefore, there is an urgent need to develop new antibacterial strategies. Herein, based on the good photothermal properties of Copper sulfide (CuS) nanoparticles under near infrared (NIR) laser, we developed a NIR-Ⅱ window triple-mode synergetic antibacterial cCuS (cationic CuS) @Vancomycin (Van) nanoplatform. In the proposed nanoplatform, the positive charge on the surface makes cCuS@Van nanoplatform show better bacterial uptake and membrane damage; vancomycin induces chemical sterilization and provides a targeting effect to the nanoplatform; combined with the strong photothermal effect and deep tissue penetration at the excitation of 1064 nm laser, cCuS@Van nanoplatform can effectively kill bacterial. The photothermal conversion efficiency of the nanoplatform can reach 49.12 % and in vitro experiments show a sterilizing rate of more than 99.5 % to staphylococcus aureus (S. aureus) at the concentration of 3.0 μM, which also demonstrated the synergistic effect of cCuS@Van nanoplatform. In addition, low cytotoxicity to human cells conforms the good biocompatibility of the as-prepared cCuS@Van nanoplatform, which endows it a good application prospect in the field of antibacterial, such as wound healing and implant sterilization.