Characterization of silver nanoparticles biosynthesized using Amaranthus cruentus

The use of plant extracts is a low-cost and green way to synthesize nanoparticles. In this research, the authors investigated the antibacterial, cytotoxic and antiangiogenic properties of silver nanoparticles (AgNPs) synthesized using Amaranthus cruentus extract. The fabricated nanoparticles were characterized by transmission electron microscopy (TEM), field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, dynamic light scattering and X-ray diffraction. The TEM results showed that the typical size of the AgNPs recorded was 15 nm. Biological tests indicated that the biosynthesized AgNPs had caused a decrease in cancerous cells (MCF-7) and had a high antibacterial activity against Escherichia coli, Staphylococcus epidermidis and Staphylococcus aureus. According to data analysis, the number and length of the blood vessels in different concentrations of AgNPs reduced significantly (depending on the dose). The chorioallantoic membrane assay revealed a large decrease in the number and length of angiogenic blood vessels in the presence of AgNPs. Real-time polymerase chain reaction and flow cytometry studies showed a dramatic increase in the gene expression of caspase-3 and caspase-8.