In vitro Antibacterial and Cytotoxic Studies of Engineered Copper Nanoparticles

Abstract

Synthesis of copper nanoparticles (CuNPs) and their complexes have growing interest in recent years due to their potential applications in nanomedicine. CuNPs and are now used as antibacterial, antiviral, anti-fungal and anti-fouling agents. Because of high sensitivity towards aggregation and oxidation, scale-up of CuNPs per batch yield remains a challenge, which dramatically alters their antibacterial and toxicological properties. Therefore, development of synthesis protocols leading to a successful scale-up of nanoparticle per batch yield without altering their antibacterial and toxicological activities remain a subject of great interest to the researchers. I have done synthesis of CuNPs scale-up of nanoparticles per batch yield (from 0.2 g to 0.4 g) that were stable against aggregation and oxidation. The antibacterial, cytotoxic and synergistic activities of as-synthesized CuNPs were evaluated on pathogenic bacteria (Escherichia coli and Proteus vulgaris) and on cancer cell lines (MCF-7 Breast cancer cell line and RAW 264.7 Murine macrophage cell line). Minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), cytoplasmic leakage, reactive oxygen species (ROS) and disk diffusion assay of CuNPs were measured, respectively. Dose-dependent cytotoxicity was evaluated by MTT, colorimetric and reactive oxygen species (ROS) assays. I have evaluated the ecotoxicity of CuNPs against soil microbes (Bacillus subtilis and Pseudomonas fluorescens) for gauging the negative impact of inadvertent release of nanoparticles in the environment. The correlation between the per batch yield of CuNPs and their antibacterial activities and cytotoxicity was also evaluated. The results indicated that scale-up of CuNPs’ yield did not significantly alter the antibacterial and cytotoxicity of nanoparticles. The ability to scale-up the nanoparticle yield with strong dose-dependent antibacterial and cytotoxicity makes CuNPs the potential candidate for the development of antimicrobial and anticancer drugs.