title: Oxidative stress-mediated selective antimicrobial ability of nano-VO2 against Gram-positive bacteria for environmental and biomedical applications.
abstract: Vanadium dioxide (VO2) is a unique thermochromic material as a result of its semiconductor-metal transition, holding great promise for energy-saving intelligent windows. Herein, pure nano-VO2 from discrete nanoparticles to continuous films were successfully deposited on quartz glass by controlling the sputtering parameters. It was demonstrated that, for Gram-positive S. aureus and S. epidermidis, the nano-VO2 could effectively disrupt bacteria morphology and membrane integrity, and eventually cause death. By contrast, the nano-VO2 did not exhibit significant toxicity towards Gram-negative E. coli and P. aeruginosa. To our knowledge, this is the first report on a selective antimicrobial effect of nano-VO2 materials on Gram-positive bacteria. Based on the experimental results, a plausible mechanism was proposed for the antimicrobial selectivity, which might originate from the different sensitivity of Gram-positive and Gram-negative bacteria to intracellular reactive oxygen species (ROS) level. Elevated intracellular ROS levels exceed the threshold that bacteria can self-regulate to maintain cellular redox homeostasis and thus cause oxidative stress, which can be alleviated by the intervention of glutathione (GSH) antioxidant. In addition, nano-VO2 did not produce significant cytotoxicity (hemolysis) against human erythrocytes within 12 h. Meanwhile, potential cytotoxicity against HIBEpiC revealed a time- and dose-dependent behavior that might be controlled and balanced by careful design. The findings in the present work may contribute to understanding the antimicrobial behavior of nano-VO2, and to expanding the new applications of VO2-based nanomaterials in environmental and biomedical fields.
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. xyliu@mail.sic.ac.cn and University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Jinhua
authors.initials: J
authors.lastname: Li
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. xyliu@mail.sic.ac.cn and University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Huaijuan
authors.initials: H
authors.lastname: Zhou
authors.affiliation: Department of Orthopaedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai 200233, China.
authors.forename: Jiaxing
authors.initials: J
authors.lastname: Wang
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. xyliu@mail.sic.ac.cn and University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Donghui
authors.initials: D
authors.lastname: Wang
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. xyliu@mail.sic.ac.cn.
authors.forename: Ruxiang
authors.initials: R
authors.lastname: Shen
authors.affiliation: Department of Orthopaedics, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, Shanghai Jiao Tong University, Shanghai 200233, China.
authors.forename: Xianlong
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. xyliu@mail.sic.ac.cn and Materials Research Institute for Sustainable Development, National Institute of Advanced Industrial Science and Technology, Nagoya 463-8560, Japan. p-jin@mail.sic.ac.cn.
authors.forename: Ping
authors.initials: P
authors.lastname: Jin
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050, China. xyliu@mail.sic.ac.cn.
authors.forename: Xuanyong
authors.initials: X
authors.lastname: Liu
mesh_terms: D000890:Anti-Infective Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D004847:Epithelial Cells / Q000187:drug effects; D004912:Erythrocytes / Q000187:drug effects; D006094:Gram-Positive Bacteria / Q000187:drug effects*; D006801:Humans; D053768:Metal Nanoparticles; D018384:Oxidative Stress; D010087:Oxides / Q000494:pharmacology*; D017968:Vanadium Compounds / Q000494:pharmacology*
chemical_list: D000890:Anti-Infective Agents; D010087:Oxides; D017968:Vanadium Compounds; C581824:vanadium dioxide