Biosynthesis, Characterization, Antimicrobial and Cytotoxic Effects of Silver Nanoparticles Using Nigella arvensis Seed Extract.

The biogenic synthesis of metal nanomaterial offers an environmentally benign alternative to the traditional chemical synthesis routes. In the present study, the green synthesis of silver nanoparticles (AgNPs) from aqueous solution of silver nitrate (AgNO3) by using Nigella arvensis L. seed powder extract (NSPE) has been reported. AgNPs were characterized by UV-vis absorption spectroscopy with an intense surface plasmon resonance band at 435 nm which reveals the formation of nanoparticles. Fourier transmission infrared spectroscopy (FTIR) showed that nanoparticles were capped with plant compounds. Transmission electron microscopy (TEM) showed silver nanoparticles, with a size of 2-15 nm, were spherical. The X-ray diffraction spectrum (XRD) pattern clearly indicates that AgNPs formed in the present synthesis were crystalline in nature. Stabilized films of exudate synthesized AgNPs were effective anti-bacterial agents. In addition, these biologically synthesized nanoparticles were also proved to exhibit excellent cytotoxic effect on a human breast cancer cell line (MCF-7) and a human colorectal adenocarcinoma cell line (HT-29). The results confirmed that the NSPE is a very good ecofriendly and nontoxic source for the synthesis of AgNPs as compared to the conventional chemical/physical methods. Therefore, N. arvensis seed provides future opportunities in nanomedicine by tagging nanoparticles with secondary metabolites.