title: Toxicity of a polymer-graphene oxide composite against bacterial planktonic cells, biofilms, and mammalian cells.
abstract: It is critical to develop highly effective antimicrobial agents that are not harmful to humans and do not present adverse effects on the environment. Although antimicrobial studies of graphene-based nanomaterials are still quite limited, some researchers have paid particular attention to such nanocomposites as promising candidates for the next generation of antimicrobial agents. The polyvinyl-N-carbazole (PVK)-graphene oxide (GO) nanocomposite (PVK-GO), which contains only 3 wt% of GO well-dispersed in a 97 wt% PVK matrix, presents excellent antibacterial properties without significant cytotoxicity to mammalian cells. The high polymer content in this nanocomposite makes future large-scale material manufacturing possible in a high-yield process of adiabatic bulk polymerization. In this study, the toxicity of PVK-GO was assessed with planktonic microbial cells, biofilms, and NIH 3T3 fibroblast cells. The antibacterial effects were evaluated against two Gram-negative bacteria: Escherichia coli and Cupriavidus metallidurans; and two Gram-positive bacteria: Bacillus subtilis and Rhodococcus opacus. The results show that the PVK-GO nanocomposite presents higher antimicrobial effects than the pristine GO. The effectiveness of the PVK-GO in solution was demonstrated as the nanocomposite "encapsulated" the bacterial cells, which led to reduced microbial metabolic activity and cell death. The fact that the PVK-GO did not present significant cytotoxicity to fibroblast cells offers a great opportunity for potential applications in important biomedical and industrial fields.
authors: Department of Civil and Environmental Engineering, University of Houston, Houston, TX 77004, USA.
authors: Isis E
authors: IE
authors: Mejías Carpio
authors: Catherine M
authors: CM
authors: Santos
authors: Xin
authors: X
authors: Wei
authors: Debora F
authors: DF
authors: Rodrigues
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000494:pharmacology / Q000633:toxicity; D001412:Bacillus subtilis / Q000187:drug effects / Q000502:physiology; D018441:Biofilms / Q000187:drug effects; D002227:Carbazoles / Q000737:chemistry; D049921:Cupriavidus / Q000187:drug effects / Q000502:physiology; D004926:Escherichia coli / Q000187:drug effects / Q000502:physiology; D006108:Graphite / Q000737:chemistry*; D051379:Mice; D041681:NIH 3T3 Cells; D053761:Nanocomposites / Q000737:chemistry* / Q000633:toxicity; D010087:Oxides / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012240:Rhodococcus / Q000187:drug effects / Q000502:physiology
chemical_list: D000900:Anti-Bacterial Agents; D002227:Carbazoles; D010087:Oxides; D011108:Polymers; C041514:carbazole; D006108:Graphite