Electrochemical assay for Heavy Metals trace in Marine Environment by The Peaks ShifT Analysis during catalysis – EMMETT

The EMMETT project proposes the development of a new electrochemical method for metal-trace analysis in the marine environment. This method is more sensitive and more specific than usual stripping techniques and will be investigated in a lab-on-chip with a view for long-term and in situ applications. To do this, the project is based on recent results obtained at the laboratory for a marine copper sensor development. This work has highlighted that following copper passive accumulation on modified electrodes, the electrocatalytic properties of the metal towards protons reduction could be used for its dosage. This analytical way presented a better sensitivity, more than 10 times compared to classical stripping technique. The uniqueness of this method is the use of the catalytical regime to measure the catalyst rather than the substrate: this is the potential measurement at the highest catalytical current density that permits to obtain the catalyst quantity pre-concentrated at the electrode. Since most of heavy metals are known to show catalytical properties for water electrocatalysis, the EMMETT project proposes to extend this methodology for iron and manganese detection, which are metals essential to phytoplankton production and usual searched elements in the marine environment. Moreover, as in situ electrochemical measurements of these elements lack alternatives to methods employing mercury electrodes, it is proposed to develop a homemade graphite-based material, that could be included in a microfluidic module made by stereolithography. The final objective of the project is to obtain a complementary module to the existent CHEMINI marine in situ chemical microanalyzer in order to detect trace metals thanks to their electrocatalytic properties, with eco-friendly material and increased sensitivity, compared to the conventional methods.