LAUSR

Abstract This work aims to assess the cytotoxicity of silver oxide and gold nanoparticles on two cancer cell cultures, human colon CaCo-2, and cervical HeLa cancer cells. Silver oxide and gold nanoparticles were synthesized using the isolated microalgae Oscillatoria sp. and Spirulina platensis. Different characterization tools (UV–Vis spectrum, XRD diffraction, TEM photography, FTIR spectroscopy, and Zeta-potential) had been used to confirm the resulted nanoparticles. Thereafter, the resulted silver oxide and gold nanoparticles were assessed as anticancer agents against human colon cancer (CaCo-2), cervical cancer (HeLa), and normal cells (WISH). The effective interaction of Oscillatoria sp. mediated Ag2O|AgO-NPs and S. platensis mediated Au-NPs against the normal human cells (WISH) and the cancer cells (CaCo-2 and HeLa), as IC50 of Ag2O|AgO-NPs recorded 147.77, 252.83, and 286.74 μg/ml for WISH, CaCo-2, and HeLa cells, respectively. IC50 for Au-NPs recorded 307.31, 311.00, and 382.90 μg/ml for WISH, CaCo-2, and HeLa cells, respectively. The safety limit against HeLa reached 98.61% by 3.906 μg/ml of Ag2O|AgO-NPs, and it recorded 93.13% by 15.625 μg/ml against CaCo-2, while the results of WISH was 51.29 % by 125.00 μg/ml. Concerning the anticancer effect of Au-NPs, the safety limit recorded 92.47% by 3.906 μg/ml against CaCo-2, while HeLa reached 93.43% by 15.625 μg/ml and WISH was 99.62% by 62.500 μg/ml. The cytotoxicity results revealed that both Oscillatoria sp. mediated Ag2O|AgO-NPs and S. platensis mediated Au-NPs caused the reduction of the colon (CaCo-2) and cervical cancer cell lines. Although the low concentrations of silver oxide nanoparticles 3.906 and 15.625 μg/ml showed the safety limit effect against HeLa and CaCo-2, they revealed no hazard on WISH cells. In conclusion, algal silver oxides and gold nanoparticles exhibited effective anticancer activities against cancer cells as a green nanotechnology application.