Development of Gold Nanoparticles Modified Electrodes for the Detection of Heavy Metal Ions

Abstract

Following the trend of developing mercury-free electrodes for environmental monitoring. Gold-based electrodes are proving to be excellent alternatives, due to their high sensitivity and selectivity especially in the monitoring of heavy metals. In this study, gold nanoparticles (AuNPs) modified screen printed carbon electrodes (SPCE) have been developed for the purpose of simultaneous detection of mercury and lead ions in water. AuNPs were synthesized using the seeding-growth method. Cyclic voltammetry (CV) was performed to investigate the electrochemical properties of the developed SPEs. AuNPs of average size of 50 nm showed optimal electroactivity. Square-wave Anodic stripping voltammetry (ASV) was used for the detection of the target heavy metals. Analysis were conducted with acetate buffer as the supporting electrolyte. Optimal concentration of acetate buffer was found at 0.2 M. The limit of detection (LOD) of Hg was 1.18 μg/L, while the LOD of Pb was 4.62 μg/L.