Phyto‐synthesis of silver nanoparticles from Tephrosia purpurea and its in‐vitro biogenic actions

Abstract

Tephrosia purpurea silver nanoparticles (TP‐AgNPs) were synthesized with water‐based leaf extract of the plant T. purpurea. UV–Vis characterization had shown the maximum absorbance at 436 nm. The surface morphology was examined via electron microscopy (FE‐SEM) analysis (average size: ~100 nm, shape: spherical). The zeta potential (ZP) of TP‐AgNPs revealed values of −41.72 mV suggesting appropriate physical stability. Besides, an X‐ray crystallography (XRD) study had shown the crystalline size of 20 nm approximately having 2θ values of 32°, 38°, 44°, 64°, and 77° for the silver crystals. The energy dispersive (EDAX) study manifests the absorption peak at 2.983 keV for TP‐AgNPs. Infrared spectroscopy analysis (Fourier‐transform infrared spectroscopy) indicated the presence of alcoholic as well as aromatic groups in the extract that took part in the stability and silver reduction mechanisms. Biologically, TP‐AgNPs had shown prominent anti‐oxidant activities against 2,2‐diphenyl‐1‐picrylhydrazyl radicals (IC50 50 μg/mL) and H2O2 radicals (IC50 106 μg/mL). It had also inhibited the proliferation of breast cell lines (MCF 7) showing total growth inhibition (TGI) at 8.2 μg/mL with the LC50 of 44 μg/mL for TP‐AgNPs. Further, hemolysis analysis revealed that TP‐AgNPs are non‐toxic to human erythrocyte cells (RBCs) as they do not cause the breakdown of RBCs. Thus, TP‐AgNPs were found to be an effective agent to be studied further for chemotherapeutic mechanisms.