On-Chip Antifouling Gel-Integrated Microelectrode Arrays for In Situ High-Resolution Quantification of the Nickel Fraction Available for Bio-Uptake in Natural Waters

Article Article scientifique Article On-Chip Antifouling Gel-Integrated Microelectrode Arrays for In Situ High-Resolution Quantification of the Nickel Fraction Available for Bio-Uptake in Natural Waters eng 2023-01-31 2023-01-31 author Creffield Sébastien Denis 876180 author Tercier Waeber Marie-Louise 0000-0002-5984-7930 22565 Département de chimie minérale et analytique (CHIAM) author Gressard Tanguy 850533 author Bakker Eric 716236 Département de chimie minérale et analytique (CHIAM) author Layglon Nicolas 0000-0001-7731-1067 953135 1346 10.3390/molecules28031346 1420-3049 https://www.mdpi.com/1420-3049/28/3/1346 <p>We aimed to monitor in situ nickel (Ni(II)) concentrations in aquatic systems in the nanomolar range. To achieve this, we investigated whether an analytical protocol for the direct quantification of cobalt (Co(II)) using adsorptive cathodic sweep voltammetry (Ad-CSV) on antifouling gel-integrated microelectrode arrays (GIME) we recently developed is also suitable for direct Ni(II) quantification. The proposed protocol consists of the reduction of the complex formed between Ni(II) (or Ni(II) and Co(II)) and nioxime adsorbed on the surface of the GIME-sensing element. The GIME enables to (i) avoid fouling, (ii) control the metal complex mass transport and, when interrogated by Ad-CSV, (iii) selectively determine the dynamic (kinetically labile Ni-nioxime) fraction that is potentially bioavailable. The nioxime concentration and pH were optimized. A temperature correction factor was determined. The limit of detection established for 90 s of accumulation time was 0.43 ± 0.06 in freshwater and 0.34 ± 0.02 nM in seawater. The sensor was integrated in a submersible probe in which the nioxime-containing buffer and the sample were mixed automatically. In situ field measurements at high resolution were successfully achieved in Lake Geneva during a diurnal cycle. The determination of the kinetically labile Ni-nioxime fraction allows one to estimate the potential ecotoxicological impact of Ni(II) in Lake Geneva. Additional Ni fractions were measured by ICP-MS and coupled to the in situ Ad-CSV data to determine the temporal Ni(II) speciation.</p> Dewey 540 LeXPLORE Swiss National Science Foundation Advanced in situ sensing systems for high-resolution speciation in aquatic ecosystems 207373 CH Projects 40 Département de chimie minérale, analytique et appliquée 145 false 772 Groupe Bakker Molecules 28 3 aa062a26-73a2-461c-8ab4-0ce2fc8f19ad Article (Published version) Public Article_scientifique_from_crossref.pdf 2498385 application/pdf CC BY-4.0 906f47c854cf250cd4ae9efe07a9dfa95d54cabbddcf2eebe2d3dd166804d706 openAccess Faculté des sciences / Section de chimie et biochimie / Département de chimie minérale, analytique et appliquée

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On-Chip Antifouling Gel-Integrated Microelectrode Arrays for In Situ High-Resolution Quantification of the Nickel Fraction Available for Bio-Uptake in Natural Waters	Molecules			2023	32	63

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Gressard, Tanguy