A gold nanocomposite made soluble In both water and oil by the addition of a second adsorption layer of poly-N-vinyl-2-pytrrolidone on gold nanoparticles that have been made hydrophobic

摘要

A kind of nanocomposite with hydrophobic nanogold as the core and an absorption layer of poly-N-vinyl-2-pyrrolidone (PVP) molecules surrounding it has been prepared. The nanocomposite can be dispersed well in both water and organic solvent. In water media it disperses over a pH range from 1 to 14, while in organic media the desorption of PVP results in the nanoparticles becoming hydrophobic; the enhancement of the viscosity caused by the PVP solution causes the hydrophobic sol to have very good kinetic stability. The particles can be switched repeatedly between hydrophobic and hydrophilic states. Transmission electron microscopy, Fourier transform infrared spectroscopy and energy dispersive x-ray analysis have been used to study the multilayer protection mechanism.