Application of Metal and Metal Oxide Nanoparticles as Potential Antibacterial Agents

Abstract

With the widespread use of antibiotics, the bacteria have evolved to build up mechanisms to resist the activity of antibiotics. The antibiotics target cell wall, protein synthesis and DNA replication, whereas microbes resist it through genetic basis or mechanistic basis of environmental resistance. The nanoparticles have shown a great potential as an alternative to antibiotics for treatment of microbial infections. Nanoparticles cause microbial inactivation via oxidative stress, dissolved metal ions or non-oxidative mechanisms and target cell barrier, bacterial protein, enzymes and DNA synthesis and its metabolism. The multiple mechanisms which nanoparticle employ simultaneously against microbes can have the potential to overcome the microbial resistance by providing the bacteria insufficient time to mutate and develop resistance. This book chapter focuses on mechanisms of antibiotic action and resistance developed by bacteria. Various metal nanoparticles (silver, copper, gold, aluminium) and metal oxides nanoparticles (copper oxide, titanium dioxide nanoparticles, zinc oxide and magnesium oxide nanoparticles) that are used for antibacterial action and impact of physicochemical properties are discussed. The chapter also elucidates the potential mode of action by various nanoparticles and impact of various important factors such as size, composition, shape, morphology, zeta potential and environmental conditions on antibacterial effectiveness.