Anodic stripping voltammetric determination of arsenic(III) using a glassy carbon electrode modified with gold-palladium bimetallic nanoparticles

A glassy carbon electrode (GCE) was modified by casting gold-palladium (Au-Pd) nanoparticles onto its surface and then used for the determination of As(III) by stripping voltammetry. The structure and electrochemical properties of the nanoparticles were characterized by UV–vis spectroscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray photoelectron spectroscopy, and cyclic voltammetry. Anodic stripping voltammetry of the modified electrode was performed in solutions of pH 4.5 containing various concentrations of arsenite. The modified GCE exhibited good response towards As(III), with a limit of detection of around 0.25 ppb which is much lower than the current EPA standard of 10 ppb. The electrode is stable and not interfered by Pb(II), Cd(II), Mn(II), and Zn(II).