title: The synergetic antibacterial activity of Ag islands on ZnO (Ag/ZnO) heterostructure nanoparticles and its mode of action.
abstract: Sliver nanoparticles (NPs) possess wonderful antibacterial activity while ZnO is a promising photocatalyst. Although it has been reported that the photocatalytic activity of Ag/ZnO heterostructure nanoparticles (HNPs) was better than that of pure ZnO NPs, the existing comparisons on their antibacterial activity were all taken between Ag-doped ZnO HNPs and pure Ag NPs (or pure ZnO NPs), and were still controversial. Ag islands on ZnO, another type of Ag/ZnO HNPs, were synthesized by a two-step preparation and characterized in this work. The antibacterial activity of as-synthesized Ag/ZnO HNPs, especially with 5.0wt.% of Ag, against Escherichia coli (ATCC 25922) and Staphylococcus aureus (ATCC 25923) was enhanced greatly in contrast with that of the simple mixture of Ag and ZnO NPs. The enhancement was found to be mainly due to the obvious increase in the reactive oxidative species (especially superoxide) and the increased damage to plasmid DNA induced by Ag/ZnO HNPs.
authors.affiliation: Department of Medical Chemistry, Tianjin Key Laboratory on Technologies Enabling Development of Clinical Therapeutics and Diagnostics (Theranostics), College of Pharmacy, Tianjin Medical University, Tianjin 300070, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhang
authors.forename: Xingjie
authors.initials: X
authors.lastname: Gao
authors.forename: Lei
authors.initials: L
authors.lastname: Zhi
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Jiang
authors.forename: Yanhua
authors.initials: Y
authors.lastname: Sun
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry* / Q000494:pharmacology*; D060326:Chemistry Techniques, Synthetic; D004249:DNA Damage / Q000187:drug effects; D004357:Drug Synergism; D004926:Escherichia coli / Q000187:drug effects; D053768:Metal Nanoparticles / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D018384:Oxidative Stress / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D012834:Silver / Q000737:chemistry / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000187:drug effects; D015034:Zinc Oxide / Q000737:chemistry / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D017382:Reactive Oxygen Species; D012834:Silver; D015034:Zinc Oxide
keywords: Ag/ZnO; Antibacterial activity; DNA damage; Heterostructure nanoparticles; Reactive oxidative species; Synergetic effect