Preparation and Characterization of Gold Nanoparticles with Different Capping Agents

ABSTRACT Biocompatible gold nanoparticles have gained considerable attention in recent years for potential applications in bio-diagnostics, gas sensing, catalysis, and nanomedicine due to their interesting size-dependent properties. In the present work a chemical reduction method is used to produce gold nanoparticles with different capping agents. These nanoparticles were prepared by reducing HAuCl4 using citrate and trialanine phosphine (THPAL) and then capping with citrate, starch, and gum arabic. This article describes a general method for the preparation of citrate-, starch-, and gum arabic–coated gold nanoparticles. Non-toxic, water-soluble THPAL was used as a reducing agent in this process. The gold nanoparticles were characterized by ultraviolet-visible (UV-Vis) spectroscopy and transmission electron microscopy.