Gold nanoclusters decorated amine-functionalized graphene oxide nanosheets for capture, oxidative stress, and photothermal destruction of bacteria

Gold nanoclusters decorated amine-functionalized graphene oxide (Au-GO-NH2) nanosheets were designed as a highly efficient visible light active antibacterial agent. This assembled nanosheet is positively charged and of high specific surface area that captures bacteria through physical adsorption and electrostatic interaction. Under visible light irradiation, this photoactive nanosheet concurrently generates massive heat and produces substantial reactive oxygen species to inactivate bacteria. In comparison with bare gold nanoclusters and amine-functionalized graphene oxides, this nanosheet appears an enhanced antibacterial activity > 5-fold towards Gram-postive and Gram-negative bacteria. Moreover, a nanosheet modified silicone surface was employed as a model of implant devices, which showed superior antibacterial efficacy against bacterial colonization in vitro. This work demonstrates that the assembled nanosheet is a promising novel strategy in the construction of next generation antimicrobial agent for synergistic bacterial capture, oxidative stress, and photothermal ablation in the biomedical and environmental fields.