Gold nanoparticle-modified sustainable plastic sensor chip for voltammetric monitoring of Hg(II)

Alexandra Karapa; Christos Kokkinos; Peter R Fielden; Sara J Baldock; Nickolas J Goddard; Anastasios Economou

doi:10.1016/j.talanta.2023.124850

Gold nanoparticle-modified sustainable plastic sensor chip for voltammetric monitoring of Hg(II)

Talanta. 2023 Dec 1:265:124850. doi: 10.1016/j.talanta.2023.124850. Epub 2023 Jun 20.

Authors

Alexandra Karapa¹, Christos Kokkinos¹, Peter R Fielden², Sara J Baldock², Nickolas J Goddard³, Anastasios Economou⁴

Affiliations

¹ Department of Chemistry, National and Kapodistrian University of Athens, Athens, 157 71, Greece.
² Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK.
³ Process Instruments (UK) Ltd, March Street, Burnley, BB12 0BT, UK.
⁴ Department of Chemistry, National and Kapodistrian University of Athens, Athens, 157 71, Greece. Electronic address: aeconomo@chem.uoa.gr.

PMID: 37354623
DOI: 10.1016/j.talanta.2023.124850

Abstract

Mercury is a toxic environmental contaminant that can cause serious health problems. This work describes a new type of eco-friendly three-electrode plastic sensor chip for the determination of trace Hg(II) by means of anodic stripping voltammetry (ASV). The sensor chip is entirely fabricated by injection moulding, which is a sustainable manufacturing method, and consists of three conductive carbon-based electrodes embedded in a plastic holder while the reference electrode is coated with Ag using e-beam evaporation. The sample is spiked with Au(III) which deposits on the working electrode in the form of gold nanoparicles during the analysis; the target Hg(II) co-deposits on the gold nanoparticles forming a Au(Hg) amalgam in situ. The accumulated Hg is stripped off the electrode and quantified by an anodic square wave potential scan. The relevant conditions and the potential interferences are investigated. The limit of detection for Hg(II) is 0.4 μg L^-1 and the repeatability at the 20 μg L^-1 Hg(III) level (n = 10) is 5.3%. The sensor is applied to water, honey, fish oil and mussel samples with recoveries between 98 and 107%.

Keywords: Anodic stripping voltammetry; Injection-moulding; Integrated sensor; Mercury; Plastic electrodes.