Biosynthesis of silver nanoparticles at room temperature using aqueous aloe leaf extract and antibacterial properties

Biosynthesized silver nanoparticles were synthesized with the aid of a novel, non-toxic, eco-friendly biological material, namely aloe leaf extract (ALE). Crushed, ultrasound treated, decolorized aqueous aloe leaf extract was used for capping silver nitrate. Silver nanoparticles were formed when the reaction conditions were altered with respect to concentration of silver nitrate, consumption of hydrazine hydrate, ALE content and incubation temperature. The colorless reaction mixtures turned brown and displayed UV-visible spectra characteristic of silver nanoparticles. Transmission electron microscope (TEM) observation revealed the predominance of silver nanosized crystallites after short incubation period. After the reaction mixtures were incubated for 30 days, the presence of silver nanoparticles was confirmed by X-ray diffraction analysis. Great antimicrobial activity against bacterial cultures was displayed by these formed silver nanoparticles. (C) 2013 Elsevier B.V. All rights reserved.