The antimicrobial activity of single and combined nanoparticles on bacterial growth

Abstract

In nanotechnology, nanoparticles (NPs) are small particles 1–100 nm in size that can occur in nature or be synthesized in a variety of ways, such as through biological or chemical processes, and come in many shapes and sizes. Based on their chemical composition, nanoparticles are classified into four categories: carbon-based NPs, organic/inorganic NPs, and composite NPs. NPs gained importance with the development of science and biotechnology due to their chemical and physical properties, which make them useful in many fields such as medicine, environmental protection, and agriculture. Furthermore, NPs exhibit antimicrobial activity against a variety of bacteria, including both gram-negative and gram-positive bacteria as well as multidrug-resistant bacteria. The results of this study showed a decrease in growth for both gram-negative bacteria E. coli and gram-positive bacteria S. aureus when exposed to increasing concentrations of copper and nickel oxide NPs. For the combined (0.8 M sodium thiosulfate, 0.02 M sodium caprylate, and 2M oxalic acid) NPs the results showed larger inhibition zone in the bacteria at the higher concentration of NPs (30 mg/mL) when applied in a well which means greater diffusion of NPs in the agar.