Silver oxide-bismuth oxybromide nanocomposites as an excellent weapon to combat with opportunistic human pathogens

Abstract Silver oxide loaded bismuth oxybromide (Ag2O/BiOBr) nanocomposite was synthesized using high efficiency solution-based method. The as-prepared samples were characterized by different analytical techniques. The synthesized nanoparticles were then evaluated for antimicrobial efficacy on opportunistic human pathogenic bacteria viz. Escherichia coli, Pseudomonas aeruginosa, Salmonella typhimurium, Klebsiella pneumonia, Aeromonas salmonicida. In the experiments, all the five strains were treated with BiOBr and Ag2O/BiOBr, in a concentration ranging from 0.5 mg/mL to 2.0 mg/mL and Ag2O/BiOBr was found to be highly effective. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Ag2O/BiOBr was 0.5 mg/mL and 1 mg/mL against E. coli, Salmonella typhimurium and Klebsiella pneumonia, 1 mg/mL and 1.5 mg/mL against Pseudomonas aeruginosa, and Aeromonas salmonicida, respectively. Only 2 h of exposure to different concentration of Ag2O/BiOBr nanocomposites completely inhibited the growth of all the tested bacterial strains showing an effective dose dependent inhibition of bacterial growth in a short time period. The results showed the potential bactericidal activity of as synthesized Ag2O/BiOBr, which could be an alternative to the conventional antimicrobial agents currently used and a perspective for the application of nano-silver with antibiotics to improve antimicrobial activity.