Abstract

• Colloidal gold nanoparticles in spherical shape had been synthesized from chloroauric acid (HAuCl4) by one of the solution method such as chemical reduction method. The colloidal gold nanoparticles were characterized with scanning electron microscopy (SEM) for morphological properties, X-ray diffraction method (XRD) for structural analysis and UV-VIS absorption spectroscopy for optical properties. It was found that the concentration of the precursors solution affected the size of the nanoparticles. In this nanoparticles fabrication method, the size of nanoparticles could be controlled by varying amount of sodium citrate. The antibacterial properties of gold nanoparticles had been studied.