Synthesis, characterization and evaluation of Co3O4 nanoparticles toxicological effect; synthesized by cochineal dye via environment friendly approach

Magnetic oxide nanoparticles (MNPs) have been extensively utilized in a wide range of biomedical applications, in order to improve the efficiency of the MNPs in therapeutic applications, there for in the present work high quality cobalt oxide magnetic nanoparticles were synthesized with a green solid state approach using cochineal powder (a natural and environmentally friendly source) as a biosynthetic precursor. This method is novel, green, simple, one step, surfactant free, solvent free, low temperature and fast. A natural complex of Co(NO3)(2) - cochineal prepared and thermally decomposed in 400, 500 and 600 degrees C. The synthesized-nanoparticles were characterized by; scanning electron microscope (SEM), X-ray diffraction pattern (XRD), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS) and vibrating sample magnetometer (VSM). MTT assay performed to determine the cytotoxicity and anticancer effect of the Co3O4 nanoparticles against 4T1 cell lines. Acridine orange/ethidium bromide staining methods, DAPI staining was applied in order to investigate the mechanism of cell death. The effect of the Co3O4 nanoparticles on oxidative stress studied as well using the H2DCF-DA assay used for the reactive oxygen species (ROS) generation study. The results demonstrate that the Co3O4 nanoparticles significantly reduced the survival percentage of 4T1 cells of breast cancer with that IC50 of 2 mg/ml. The dominant mechanism of cell death was apoptosis, along with an increase in cellular oxidative stress. Therefore, the Co3O4 nanoparticles prepared here can be used as a chemotherapeutic agent against invasive breast cancer cells. However, further in vivo study is required to confirm its effect. (C) 2019 Elsevier B.V. All rights reserved.