Chemical synthesis of metal and metal oxide nanoparticles and their antibacterial activity against pathogenic bacteria

Abstract

The increasing emergence of bacterial resistance against antibiotics or antibacterial drugs has challenged the development of antibacterial agents like nanoparticles which have received increased attention due to their antibacterial activity against pathogenic bacteria. In this investigation, zinc oxide, copper oxide, and silver (ZnO, CuO, and Ag) nanoparticles were chemically synthesized by sol-gel, wet chemical precipitation, and chemical reduction procedures, respectively. Characterization of nanoparticles was performed using UV-Visible and Fourier-Transform Infrared (FTIR) spectroscopy. Antibacterial activity of nanoparticles was analyzed against Staphylococcus aureus and Salmonella typhi. UV-Visible spectroscopy of ZnO, CuO, and Ag nanoparticles showed peaks at 375, 225, and 400 nm, respectively, and indicated optical properties of the nanoparticles, thereby confirming their formation. FTIR analysis showed presence of Zn-O and Cu-O bonds in ZnO and CuO nanoparticles, respectively, and various functional groups in Ag NPs. Antibacterial studies conducted against S. aureus and S. typhi reflected no antibacterial activity by ZnO and CuO nanoparticles individually, while Ag NPs showed good antibacterial effects against both pathogenic bacteria. Additionally, the antibacterial activity of ciprofloxacin impregnated with Ag NPs against S. aureus showed a synergistic effect.