In vitro evaluation of anticancer and antibacterial activities of cobalt oxide nanoparticles

Cobalt oxide nanoparticles (Co3O4-NPs) were synthesized using simple urea-based thermal decomposition method. Phase purity and particle size of as-synthesized nanoparticles were characterized through X-ray diffraction pattern (XRD) and transmission electron microscopy. Through XRD morphology of the Co3O4-NPs was found to be variable in size with range of 36 nm. In our present study, we explored the potential cytotoxic and antibacterial effects of Co3O4-NPs in human colorectal types of cancerous cells (HT29 and SW620) and also nine Gram-positive and Gram-negative bacteria. Co3O4-NPs showed promising anticancer activity against HT29 and SW620 cells with IC50 value of 2.26 and 394.5 μg/mL, respectively. However, no significant effect of Co3O4-NPs was observed against bacterial strains. Furthermore, a detailed study has been carried out to investigate the possible mechanism of cell death in HT29 cancer cell line through the analysis of expression level of anti-apoptotic Bcl2 and BclxL markers. Western blot analysis results suggested significant role of Co3O4-NPs exposure in cell death due to apoptosis.