, Volume 43, Issue 4, pp 234-240,
Open Access This content is freely available online to anyone, anywhere at any time.

Facile green synthesis of gold nanoparticles with gum arabic as a stabilizing agent and reducing agent


A facile, completely green, and cheap route for the synthesis of Au nanoparticles at 25–75° has been developed by using only hydrogen tetrachloroaurate as the precursor and gum arabic (GA) simultaneously as a reducing agent and a stabilizing agent. No extra reagents are needed. From the analyses of UV/VIS absorption spectra, TEM, HRTEM, SAED, and XRD patterns, the formation of Au nanoparticles with a fcc structure was recognized. The synthesis reaction was usually finished in 2–4 h. Increasing the reaction temperature increased the formation rate but had no significant effect on the optical property and size of Au nanoparticles. With increasing Au(III) ion concentration or GA concentration, the mean diameter of Au nanoparticles slightly increased. Also, the particle size distribution became broader at higher Au(III) ion concentration or lower GA concentration due to the insufficient protection. Although raising the GA concentration was helpful to reduce Au(III) ions completely and stabilize the Au nanoparticles, too high GA concentration was not suitable for the stabilization of Au nanoparticles because the increased intermolecular force of GA might hinder the dispersion of Au nanoparticles. Furthermore, the resultant Au nanoparticles were found to remain highly stable in the NaCl solution.

Dr. Dong-Hwang Chen is a distinguished professor of Chemical Engineering Department at National Cheng Kung University (Taiwan). His research works include the synthesis of nanoparticles, the fabrication of composite nanoparticles and thin films, the development of nanomaterials for electromagnetic wave absorption, as well as the fabrication and applications of functionalized magnetic nanocarriers in separation, catalysis, and biomedicine.
Mr. Chien-Chen Wu currently works as a PhD student in the laboratory of Prof. Chen in Department of Chemical Engineering at National Cheng Kung University (Taiwan). His research focuses on the synthesis and applications of nanoparticles and functional composite nanoparticles.