Gold Nanoparticles-Modified Screen-Printed Electrode for Determination of Pb(II) Ion Using Linear Sweep Anodic Stripping Voltammetry

A new electrochemical sensor based on screen-printed electrode (SPE) gold nanoparticles (AuNPs) has been fabricated for determination of Pb(II) ion by anodic stripping voltammetry in Tris-HCl (pH 5) solution. In this medium, Pb(II) ion was preconcentrated on SPE modified with AuNPs and stripped anodically in linear sweep voltammetry mode, with a peak potential at -0.5 V. The effect of various parameters (pH, supporting electrolyte composition, deposition potential, deposition time, and scan rate) on the sensitivity was studied. Under controlled deposition time for 240 s, the detection limit (3 s) was 1.3-ng ml^-1 Pb(II) and the calibration curve was linear up to 30 μg ml^-1. The procedure was applied to the determination of Pb(II) ion in tap water with satisfactory results. The prepared modified electrode shows several advantages such as high sensitivity, long-time stability, wide linear range, and ease of preparation.