Antibacterial Activity of Reduced Graphene Oxide

Figure 3

Cell viability assessment of the model bacterium E. coli upon exposure to increasing concentration of RGO particles. (a) Surface colony studies using the agar assay. LB agar containing E. coli was exposed to sterile filter papers (3 cm diameter) previously soaked in increasing concentrations of RGO particle suspension (0, 10, 50, 100, 200, and 400 μg/mL) for 6 h, and the agar was then incubated overnight at 37°C. (b) Turbidity of E. coli (in saline and minimal presence of culture medium) exposed to increasing concentrations of RGO particles, after 16 h incubation at 37°C, 250 rpm. (c) Cell viability assessment using the agar colony counting method, after incubating the cells with RGO saline suspensions for 3 h at 37°C/250 rpm. For each RGO concentration, the data represents the percentages of viable cells at the end of the exposure relative to those of at time zero. The data is the average of three biologically independent experiments (different bacterial inocula and particle preparations), each with three technical replicates (). The error bars represent the standard error of mean (SEM).

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