CuO and Au-CuO nanoparticles mediated by Stigmaphyllon ovatum leaf extract and their anticancer potential

The synthesis of nanoparticles by green methods, utilizing the extracts from plants has become viable alternative routes for nanomaterial synthesis. The method avoids the expensive and toxic materials used during chemical syntheses. The incorporation of plant extracts with favourable biological properties into nanoparticles has beneficial relevance in the biomedical field. In this study, CuO and Au-CuO nanoparticles were synthesized using the aqueous extract of the Stigmaphyllon ovatum plant and characterised. Optical studies produced peaks around 290 and 670 nm in both nanomaterials, and can be attributed to electron transition and the surface plasmon bands of Cu. The spectra of the Au-CuO nanohybrid showed a broad band around 564 nm due to Au doping. Band gap energies of 3.25 and 3.17 eV were obtained for the CuO and Au-CuO nanohybrids, respectively. The photoluminescence spectra at an excitation wavelength of 200 nm gave different peaks with the near band edge at 300 nm. The synthesized nanoparticles were further evaluated as potential anticancer agents in HeLa cells, and exhibited good anticancer potency with Au-CuO having the greatest activity. The IC50 values for CuO, Au-CuO nanomaterials and the control drug (5-fluorouracil) were 12.3, 112 and 40 mu M respectively.