Antibacterial Activity of Partially Oxidized Ag/Au Nanoparticles against the Oral Pathogen Porphyromonas gingivalis W83

Figure 6

Growth curves of P. gingivalis W83 stressed with 0.25 mM H₂O₂ in the presence of aerobically prepared Ag and Ag/Au nanoparticles. Bacterial growth over a 24-hour period was assessed by measuring the absorbance of cultures at 600 nm for specific intervals. Actively growing P. gingivalis W83 (OD₆₀₀ ≈ 0.2) was challenged with maltose coated Ag (≈0.2 nM, 400 μL; ) or glutathione capped Ag/Au (Au : Ag ≈ 0.2; ≈0.4 nM, 400 μL; ) nanoparticles in 5 mL total volume. Glutathione capping was done by method II. Hydrogen peroxide was added when of W83 control was ≈0.2. Error bars represent the standard deviation of three experiments.