Synthesis of gold nanoparticles using glutamic acid as a reductor and capping agent

The synthesis of gold nanoparticles (AuNPs) was carried out by reacting chloroauric acid AuCl4- and glutamic acid solution in a water bath at 80 °C. The reaction was confirmed by the color change from colorless solution into pink. Various concentrations of the glutamic acid solution, reaction times and pH were examined to determine the optimum condition of AuNPs synthesis. The AuNPs colloid was characterized by UV-Visible spectrophotometer at wavelength 350-800 nm, particle size analyzer (PSA) and transmission electron microscope (TEM). The optimum synthesis condition for obtained AuCl4- was 4 mM glutamic acid solution at pH 11 and 60 min reaction. TEM results showed that the particles were round in shape with the article size indicated by PSA was 40 nm. © 2020 Trans Tech Publications Ltd, Switzerland.