Camellia Sinensis Leaf Extract Mediated Synthesis of Copper Oxide Nanostructures for Potential Biomedical Applications

Abstract

Despite the great progress in nanotechnologies, to date, there is still a lack of definite knowledge on the effects of CuO nanoparticles on cancer cell lines. In this present work, CuO nanoparticles were synthesized using Tea (Camellia sinensis) leaf extract. The devised method provides a simple, cost-effective aqueous means of producing spherical copper oxide nanoparticles. Preliminary characterization of green synthesized CuO NPs was carried out using UV-Vis spectroscopy, XRD, FT-IR, Zeta Potential, TEM and SAED analysis. The average crystallite size of the CuO nanoparticles is estimated to be 22.44 nm and the band gap for CuO nanoparticles was found to be 1.54 eV which are higher than bulk CuO. TEM images of CuO NPs shows a spherical morphology with moderate size distribution of larger nanoparticles due to agglomeration. The average particle size obtained from TEM is in the range of 25-32 nm which agrees well with the crystallite size calculated from XRD. CuO NPs has negative zeta potential of -70.2 mV which could keep it suspension stability for longer period of time. The antibacterial activity test results revealed a highest inhibition zone of 21 mm for gram positive S.aureus. Gram positive Staphylococcus aureus and gram negative Klebsiella pneumonia depicted highest sensitivity to nanoparticles compared to other strains and was more adversely affected by the copper oxide nanoparticles. CuO NPs have been tested for their potent cytotoxic activity against MCF-7 (breast cancer cells) using MTT assay. CuO NPs at the concentration of 50 μg/ml decreased the viability of MCF-7 cells by 50%.The quantification of cellular CuO NPs uptake using the imaging revealed a clear dose dependent toxic activity