【摘 要】
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Graphene,as a typical two-dimensional layered material,possesses extraordinary electronic and optical properties that render it for a wide range of potential applications including biomedicine[1].Insp
【机 构】
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State Key Laboratory of Silicon Materials,MOE Key Laboratory of Macromolecular Synthesis and Functio
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Graphene,as a typical two-dimensional layered material,possesses extraordinary electronic and optical properties that render it for a wide range of potential applications including biomedicine[1].Inspired by the graphene research and development,graphene-like two-dimensional materials(2DMats)also show application potentials in biomedicine due to their unique properties[2-4].However,environmental and biological infuences of these 2DMats remain to be uncovered.Here we reported the antibacterial activity of two-dimensional(2D)chemically exfoliated MoS2(ce-MoS2)sheets[5].We found that the antibacterial activity of ce-MoS2 sheets was much more potent than that of the raw MoS2 powders used for the synthesis of ce-MoS2 sheets possibly due to the 2D planar structure(high specifc surface area)and higher conductivity of the ce-MoS2.We investigated the antibacterial mechanisms of the ce-MoS2 sheets and proposed their antibacterial pathways.We found that the ce-MoS2 sheets could produce reactive oxygen species(ROS),different from previous report on graphenebased materials.Particularly,the oxidation capacity of the ce-MoS2 sheets toward glutathione oxidation showed a time and concentration dependent trend,which is fully consistent with the antibacterial behaviour of the ce-MoS2 sheets.The results suggest that antimicrobial behaviors were attributable to both membrane and oxidation stress.The antibacterial pathways include MoS2-bacteria contact induced membrane stress,superoxide anion(O2·–)induced ROS production by the ce-MoS2,and the ensuing superoxide anion-independent oxidation.Our study thus indicates that the tailoring of dimension of nanomaterials and their electronic properties would manipulate antibacterial activity.
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