Preparation of Monotheca buxifolia Leaves Mediated Silver Nanoparticles and Study of Their Biological Activities

摘要

In the present study, M. buxifolia mediated silver nanoparticles (AgNPs) were synthesized by mixing different volumes of the plant extract and silver nitrate solutions. The prepared AgNPs were characterized by UV-spectrophotometry, scanning electron microscopy (SEM), energy dispersive X-ray (XRD) analysis, thermal gravimetric analysis (TGA), energy dispersive X-ray (EDX) analysis, fourier transform infrared (FTIR) microscopy, and a master size analysis. The prepared nanoparticles and extracts were evaluated for their anti-microbial and anti-oxidant potentials as well. UV-spectrophotometry showed that a ratio 1 : 10 of the M. buxifolia leaves aqueous extract to a silver solution was best for the AgNPs production. The size of AgNPs was found to be 45 nm, measured through SEM. The presence of silver in the prepared AgNPs was confirmed through EDX (peak at 3.4 keV). The crystalline nature and sizes of particles were determined by XRD while the particles size distribution by the master sizer, and the results were compared with those of SEM. TGA results showed a weight loss due to a loss of the moisture content in AgNPs. The IR spectra further confirmed the presence of Ag in the prepared nanoparticles, which was evident from a silver oxide peak in the spectrum. The AgNPs were found to be highly effective against Gram positive bacteria as compared to ethanolic, methanolic, chloroform, and ethyl acetate extracts. Gram negative bacteria showed less sensitivity to AgNPs whereas similar results were obtained against different tested species of fungi. Comparatively, AgNPs were more potent scavenger of the free radical than the tested extracts.