A facile and effective technique for the synthesis of thiol-modified Au/alginate nanocomposite and its performance in stabilizing Pickering emulsion

Synthesis of thiol-based ligand-modified Au/alginate was successfully performed using simple, facile and effective technique, with the aid of microwave irradiation for completing the reduction of gold precursor. The nanocomposite has lower hydrophilicity compared to that of unmodified Au/alginate, as shown by the decrease in surface tension and increase in contact angle to water. Type and concentration of thiol-based ligand greatly influenced the hydrophilicity. By employing mercaptoundecanoic acid (MUA) and dodecanethiol simultaneously as thiol-based ligand modifier for Au/alginate, the as-prepared nanocomposites have the capability to stabilize Pickering O/W (oil-in-water) emulsion of chloroform in water. Nanocomposite concentration and pH significantly affected emulsification capability and emulsion stability.