Anticancer Activity of Lichen Extract (Usnea sp.) Based Synthesized Ag@ZnO Bimetallic Nanocomposite ^†

Bimetallic nanoparticles (NP) have improved properties such as antimicrobial, anticancer and photocatalytic activity due to the synergistic effects of their components. Unmet needs of the current cancer treatments encourage researchers for the new treatment approaches especially natural products. In this study, we aimed to investigate the antiproliferative effects of Ag@ZnO NP on the SH-SY5Y human neuroblastoma cell line. Ag@ZnO NP was dispersed in distilled water via ultrasonication and diluted with the medium as the 5, 10, 25, 50, 100, 200 and 400 μg/mL final concentrations. The cell viabilities were investigated by MTT test at 24th hours of Ag@ZnO NP treatments. In MTT test, the lower concentrations of Ag@ZnO NP (5, 10, 25 μg/mL) increased the cell viability (p < 0.01, p < 0.01 and p < 0.05, respectively) whereas it was markedly decreased (p < 0.001) the cell viabilities at higher concentrations (100, 200 and 400 ug/ml) compared with the control group. Our results showed that Ag@ZnO NP has antiproliferative effects on SH-SY5Y cells whereas it increases cell proliferation in the low dose. The effects in the low dose may depend on its activation of compensatory mechanisms in the cell. We have thought that it is worthwhile to research its anticancer potential on the different cancer cell lines.