Facile Preparation of Gold Nanoparticle Modified Pencil Graphite Electrode

Abstract

The purpose of this research was to prepare gold nanoparticle (AuNP) modified disposable pencil graphite electrode (PGE). The AuNP was prepared using trisodium citrate reduced gold ion solution. The PGE surface modification was carried out by immersing a bare PGE in poly (diallyldimethylammonium chloride) (PDDA) and then in AuNP solution at room temperature. The characterization of the bare and modified PGE surfaces was carried out using field emission scanning electron microscopy (FESEM) and cyclic voltammetry in the presence of 0.1 M NaOH. The electrochemical behavior of the modified PGE electrode was investigated using cyclic voltammetry, and impedance spectroscopy in the presence of 5 mM [Fe (CN)6]3-/4- redox probe solution. The obtained result indicated that the modification of AuNP on the PGE surface provided a good electrochemical signal. In order to obtain more sensitive electrochemical signals, the effect of adsorbed AuNP on the PGE surface was also studied.