Abstract
The present manuscript demonstrates one pot, simple, rapid, reliable and ecofriendly approach for the synthesis of antibacterial and photo catalytically active silver nanoparticles (AgNPs) using neem leaves. Aqueous extract of carefully weighed (10 gm) amount of neem leaves when added to aqueous precursor (1 mM) salt silver nitrate (AgNO3) led to the ultra-fast synthesis of profuse amounts of extracellular almost monodispersed, spherical silver nanoparticles in just 30 s. The entire reaction was completed within 12 min as can be confirmed by typical Surface Plasmon resonance (SPR) of silver nanoparticles (centered at 425 nm). The as synthesized silver nanoparticles were 3–5 nm having 3 nm as average size. The nanoparticles were characterized using standard analytical techniques such as UV–visible spectroscopy, X-ray diffraction (XRD), Transmission Electron Microscopy (TEM) and Fourier Transform Infrared Spectroscopy (FTIR). The as synthesized silver nanoparticles were found to be toxic against gram positive bacteria Bacillus thuringiensis kurstaki, Bacillus subtilis with zone of inhibition 15 and 20 mm respectively as well as gram negative bacteria such as Enterobacter clocae and Xanthomonas with zone of inhibition 18 and 14 mm respectively. These nanoparticles were also found to be photocatalytically active against organic dye such as Congo red and Potassium permanganate.