Green Synthesis and Characterization of Gold Nanoparticles Using Chitosan as the Reducing and Stabilizing Agent

Abstract

The gold nanoparticles (AuNPs) were prepared with chitosan as stabilizer and reducing agent through a one-step green method. The size and morphology of AuNPs were characterized by UV-Vis spectra and transmission electron microscopy (TEM). The effects of reaction temperature, HAuCl4 concentration, concentration and molecular weight of chitosan on the size and morphology of synthesized AuNPs were studied. According to the results, the spherical AuNPs with the average particle size around 10 nm could be prepared by 1 mL 1.0 mmol/L HAuCl4 and 3 mL 0.01%(w/v) chitosan with molecular weight in the range from 48.75 to 3.99 kDa at 70oC. The reducing ability of chitosan for Au3+ was enhanced with the molecular weight decrease.