Gold nanoparticles-modified screen-printed carbon electrodes for anodic stripping voltammetric determination of mercury in ambient water samples

We present here a simple, fast and cheap procedure for the determination of Hg(II) by square wave anodic stripping voltammetry (SWASV) at a commercial gold nanoparticles-modified screen-printed carbon electrodes (AuNPs-SPCEs), as a tool for environmental waters monitoring. The advantages of electrode nanostructuration are exploited, e.g. no stirring for the deposition step is needed. The surface of the gold nanostructured screen-printed carbon electrodes was characterized using SEM, XPS and electrochemical methods. All experimental variables involved in the voltammetric stripping method were optimized to develop a reliable method capable of measuring dissolved mercury in the low ng/mL range. The proposed method was tested with the NIST 1641d Mercury in Water Standard Reference Material with good agreement. The applicability of the AuNPs-SPCEs for Hg(II) determination in real ambient water samples, namely rain water, river water and industrial waste water, without any sample pretreatment, was successfully demonstrated.