One-step synthesis of Phyto-polymer coated gold nanospheres as a delivery system to enhance resveratrol cytotoxicity.

This study introduces a simple method for one-step synthesis of highly stable non-toxic polymer-coated gold nanospheres for use in drug delivery, focuses on the ability of chloroauric acid to induce polyphenols polymerization, puts up an easy procedure for loading hydrophobic drugs onto gold nanoparticles with ultra-high loading efficiency and studies the cytotoxicity of free and gold nanoparticles-loaded resveratrol. Gold nanospheres were synthesized simply by direct reaction between resveratrol itself and chloroauric acid in aqueous medium. Synthesized gold nanospheres exhibited high stability in both aqueous and ethanolic solutions. UV-visible spectrum showed that the synthesized gold nanospheres have maximum absorption at 532 nm. TEM imaging, mass and FT-IR spectrometry revealed the presence of a distinct polymeric shell around each nanoparticle. Resveratrol, as a chemopreventive agent, was loaded onto the synthesized gold nanospheres with an ultra-high loading capacity (11.6% w/w). Free resveratrol, free gold nanospheres and resveratrol-loaded gold nanospheres were examined for cytotoxicity on HepG2 cell line where cytotoxicity of loaded resveratrol was dramatically enhanced to reach about nine folds as that of free resveratrol at the same concentration.