title: Graphene oxide-silver nanocomposite as a highly effective antibacterial agent with species-specific mechanisms.
abstract: Recently, graphene oxide (GO) based nanocomposites have raised significant interests in many different areas, one of which being antibacterial agents where sliver nanoparticle (AgNPs) anchored GO (GO-Ag) has shown promising potential. However, to our best knowledge, factors affecting its antibacterial activity as well as the underlying mechanism remain unclear. In this study, we fabricate GO-Ag nanocomposites with different AgNPs to GO ratios and carefully investigate their antibacterial activities against both the Gram-negative (G-) bacteria Escherichia coli ( E. coli ) and the Gram-positive (G+) bacteria Staphylococcus aureus ( S. aureus ). We discover that, compared to AgNPs, GO-Ag nanocomposite with an optimal ratio of AgNPs to GO is much more effective and shows synergistically enhanced, strong antibacterial activities at rather low dose (2.5 μg/mL). The GO-Ag nanocomposite is more toxic to E. coli than that to S. aureus . The antibacterial effects of GO-Ag nanocomposite are further investigated, revealing distinct, species-specific mechanisms. The results demonstrate that GO-Ag nanocomposite functions as a bactericide against the G- E. coli through disrupting bacterial cell wall integrity, whereas it exhibits bacteriostatic effect on the G+ S. aureus by dramatically inhibiting cell division. Our work not only highlights the great promise of using GO-Ag as a highly effective antibacterial agent but also provides more in-depth understandings of the interactions between microorganisms and GO-based nanocomposites.
authors.affiliation: Institute of Functional aNano & Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials & Devices, Soochow University, Suzhou, Jiangsu 215123, China.
authors.forename: Jia
authors.initials: J
authors.lastname: Tang
authors.forename: Qian
authors.initials: Q
authors.lastname: Chen
authors.forename: Ligeng
authors.initials: L
authors.lastname: Xu
authors.forename: Shuai
authors.initials: S
authors.lastname: Zhang
authors.forename: Liangzhu
authors.initials: L
authors.lastname: Feng
authors.forename: Liang
authors.initials: L
authors.lastname: Cheng
authors.forename: Huan
authors.initials: H
authors.lastname: Xu
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Liu
authors.forename: Rui
authors.initials: R
authors.lastname: Peng
mesh_terms: D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology*; D002470:Cell Survival / Q000187:drug effects; D004926:Escherichia coli / Q000187:drug effects; D006108:Graphite / Q000737:chemistry / Q000494:pharmacology*; D057809:HEK293 Cells; D006801:Humans; D050296:Microbial Viability / Q000187:drug effects; D053761:Nanocomposites / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry / Q000494:pharmacology*; D012834:Silver / Q000737:chemistry / Q000494:pharmacology*; D013045:Species Specificity; D013211:Staphylococcus aureus / Q000187:drug effects
chemical_list: D000900:Anti-Bacterial Agents; D010087:Oxides; D012834:Silver; D006108:Graphite