Preparation and antibacterial properties of water-soluble Ag nanoparticles

Abstract

Water-soluble surface modified silver nano particles were synthesized by liquid phase reduction with tannic acid as the reduct ant and polyvinyl pyrrolid one (PVP) as the surface modification agent. The structure and morphology of the as-synthesized powders were investigated by X-ray powder diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible (UV-Vis) absorption spectroscopy, and Fourier-transform infrared (FTIR) spectrometry. The antibacterial activity of the water soluble Ag nano particles against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was investigated by broth dilution. The stable dispersion duration of the as-synthesized Ag nano particles in water was also determined. A mechanism for PVP modified Ag nano particle formation is proposed. The results show that the as-synthesized PVP modified Ag nano particles have a face-centered cubic crystalline structure. The average diameter of the Ag nano particles ranges from 15 to 17 nm. The assyn the sized powders have good solubility in water over a long period of time. PVP modified Ag nano particles exhibit good antibacterial properties against E. coli and S. aureus. This simple and mild preparation method can be easily increased to an industrial scale process and, therefore, PVP modified Ag nano particles are potentially a new type of antibacterial. © Editorial office of Acta Physico·Chimica Sinica.