The Antioxidant Activity and Cytotoxic Effects of Amaranthus cruentus-Biosynthesized Silver Nanoparticles Toward MCF-7 Breast Cancer Cell Line

Silver nanoparticles (AgNPs) have grabbed special attention owing to their exclusive structural features. Green synthesis (i.e., plant-mediated) of AgNPs is an efficient and cost-effective method with widespread clinical applications. Therefore, the present study aimed to synthesize AgNPs based on green synthesis method employing the seed extracts of Amaranthus cruentus and to investigate the antioxidant and cytotoxic activities of the biosynthesized AgNPs. The Ag-NPs were biologically synthesized using the A. cruentus extract which served as a reducing agent. Then, the synthesized Ag-NPs were visualized by transmission electron microscopy. Next, the antioxidant activity of the synthesized Ag-NPs was evaluated by DPPH and ABTS methods. Finally, the cytotoxicity of AgNPs was investigated against MCF-7 breast cancer cell line using MTT assay. The mean diameter of the synthesized Ag-NPs ranged from 20 to 40 nm. In addition, the IC50 of free radical scavenging activity of the Ag-NPs were obtained as 500 µg/mL (DPPH) and 400 µg/mL (ABTS). Further, the AgNPs showed time and dose-dependent cytotoxicity against MCF-7 cells. Eventually, at the 24-hour exposition to the 80 µg/mL dose of AgNPs, the viability of cancerous cells was 19% plunging to 2.03% and 1.9% after 48 hours and 72 hours, respectively. In general, plant extracts can serve as facile and eco-friendly alternatives to hazardous methods for synthesizing the metal nanoparticles. Therefore, the A. cruentus biosynthesized Ag-NPs can be utilized in medicine for various purposes due to their low toxicity and appropriate antioxidant activity.