The aim of this study was to evaluate the antibacterial properties of graphene oxide (GO) against Enterococcus faecalis in vitro conditions and when used to coat dentin surface to prevent E. faecalis adhesion. The ATCC strain of E. faecalis 29212 has been used to perform a viability test. The pellet was suspended in ultrapure water, NaCl, PBS buffer, CaCl₂ and MgCl₂, Luria−Bertani broth solutions. The viability was evaluated by the colony forming unit counting method. Atomic force microscopy images and the measure of surface zeta potential variation were analyzed. Dentin discs were covered with a film of GO (n = 15) or were not treated (n = 15). Bacterial suspension was added to each sample of dentine discs and microbial counts were calculated. Statistically significant differences between two groups were assessed by a two-tailed unpaired t-test. Bacteria cell morphology was investigated with scanning electron microscopy. The highest growth inhibition was obtained in ddH₂O and CaCl₂ solution while, in PBS and NaCl, GO had poor antibacterial efficacy with a growth enhancing effect in the latter. GO on dentin discs demonstrated high antibacterial activity. GO film has demonstrated acceptable adhesion properties to root dentin and a role in the inhibition of bacterial film proliferation and biofilm formation.

中文翻译：

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氧化石墨烯对粪肠球菌的抗菌和抗菌膜特性


本研究的目的是评估氧化石墨烯 (GO) 在体外条件下以及用于涂覆牙本质表面以防止粪肠球菌粘附时对粪肠球菌的抗菌特性。粪肠球菌29212 的 ATCC 菌株已用于进行活力测试。将沉淀悬浮于超纯水、NaCl、PBS缓冲液、CaCl ₂和MgCl ₂ 、Luria-Bertani肉汤溶液中。通过菌落形成单位计数法评价活力。分析了原子力显微镜图像和表面 zeta 电位变化的测量。牙本质盘覆盖有 GO 薄膜（ n = 15）或不进行处理（ n = 15）。将细菌悬浮液添加到每个牙本质盘样品中并计算微生物计数。通过双尾未配对t检验评估两组之间的统计学显着差异。用扫描电子显微镜研究细菌细胞形态。 GO在ddH ₂ O和CaCl ₂溶液中具有最高的生长抑制作用，而在PBS和NaCl溶液中，GO的抗菌效果较差，而后者具有生长促进作用。牙本质盘上的 GO 表现出很高的抗菌活性。 GO 膜已表现出对牙根牙本质可接受的粘附性能，并具有抑制细菌膜增殖和生物膜形成的作用。