title: Determination of mercury(ii) in water at sub-nanomolar levels by laser ablation-ICPMS analysis of screen printed electrodes used as a portable voltammetric preconcentration system.
abstract: Environmental pollution by mercury in ambient water samples is a recognized problem worldwide. Sample preservation and transport to the laboratory lead to uncertain analytical results. This study outlines the development of a procedure for on-site electrodeposition of mercury from water samples on a screen-printed gold electrode (SPGE) using portable voltammetric techniques. Once in the laboratory, Hg is analyzed by laser ablation inductively coupled plasma-mass spectrometry (LA-ICPMS) in order to ensure that the required sensitivity and precision levels for environmental sample analysis are reached. A new ablation chamber was intentionally designed for the analysis of SPGE's gold electrode. This cell has a small internal volume of 15 cm3and the SPGE device perfectly fits inside. This design assures signal stability, avoids elemental fractionation and reduces wash-out time to a few seconds, reducing the analysis time considerably. The proposed method is capable of measuring dissolved mercury at the ng L-1level (quantification limit 200 ng L-1) with good precision (RSD < 7.6%). The proposed method was tested with the NCS ZC 76303 (NIM-GBW08603) Mercury in water Certified Reference Material.
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, UPV/EHU, 01006 Vitoria-Gasteiz, Spain. r.barrio@ehu.es.
authors.forename: Zuriñe
authors.initials: Z
authors.lastname: Abrego
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, UPV/EHU, 01006 Vitoria-Gasteiz, Spain. r.barrio@ehu.es.
authors.forename: Nora
authors.initials: N
authors.lastname: Unceta
authors.affiliation: Alava Central Service of Analysis, SGIker, Lascaray Research Center, University of the Basque Country, UPV/EHU, Vitoria-Gasteiz, Spain.
authors.forename: Alicia
authors.initials: A
authors.lastname: Sánchez
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, UPV/EHU, 01006 Vitoria-Gasteiz, Spain. r.barrio@ehu.es.
authors.forename: Alberto
authors.initials: A
authors.lastname: Gómez-Caballero
authors.affiliation: Departament of Graphic Design and Engineering Projects, EUI, University of the Basque Country, UPV/EHU, 01006 Vitoria-Gasteiz, Spain.
authors.forename: Luis Maria
authors.initials: LM
authors.lastname: Berrio-Ochoa
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, UPV/EHU, 01006 Vitoria-Gasteiz, Spain. r.barrio@ehu.es.
authors.forename: M
authors.initials: M
authors.lastname: Aranzazu Goicolea
authors.affiliation: Department of Analytical Chemistry, Faculty of Pharmacy, University of the Basque Country, UPV/EHU, 01006 Vitoria-Gasteiz, Spain. r.barrio@ehu.es.
authors.forename: Ramón J
authors.identifier: http://orcid.org/0000-0002-1685-6685
authors.initials: RJ
authors.lastname: Barrio