In vitro assessment of Ag₂O nanoparticles toxicity against Gram-positive and Gram-negative bacteria

Abstract

In view of antibiotic resistance among pathogens, the present study is to address the toxicity of Ag₂O nanoparticles against the Gram-positive and Gram-negative bacteria through in vitro assays. The preliminary screening by agar diffusion assay confirms the antibacterial activity of Ag₂O nanoparticles against all the test bacteria. Comparative antibacterial activity of Ag₂O nanoparticles and respective antibiotics reveals their broad range of activity and lower inhibitory dose against the used bacterial strains. Further, they can inhibit E. coli with an effective dose of 0.036 mg/ml within 1 h of exposure time as determined by luciferin based ATP assay. Moreover, the Ag₂O nanoparticles exhibit higher antibacterial efficacy against Gram-negative bacteria than Gram-positive bacteria, as revealed by their MIC & MBC values. Therefore, Ag₂O nanoparticles pave the way for a new generation of antibacterial agents against the emerging multidrug resistant pathogens.