L’ICP-MS ou Spectrométrie de masse à plasma à couplage inductif est une méthode de spectrométrie de masse (SM) qui utilise comme source d’ionisation un plasma à couplage inductif (ICP, inductively coupled plasma). L’ICP ou torche à plasma est utilisée 
pour sa capacité à générer, à partir des espèces élémentaires présentes dans un échantillon, des ions qui sont ensuite dirigés vers un spectromètre de masse qui se comporte comme un filtre en séparant les ions en fonction de leur rapport masse/charge ( m/z). Cette technique séparative permet l’identification et la quantification de nombreux éléments tels que Zn, Cu, Se, Al, Mn, Hg, Cd, Fe, Cr, V, Co et Ni
Une équipe de chercheurs espagnols a optimisé une méthode de dosage simultané de 12 éléments dans des échantillons de plasma humain.
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In this work, trace Hg2+ in environmental water samples was first preconcentrated by dispersive liquid–liquid microextraction (DLLME), and then was colorated by one common rhodamine B thiolactone (RBT) probe for visual and fluorescence detection. In this way, a highly sensitive and selective method was developed for field monitoring of Hg2+ in environmental waters. The color of RBT test solution could change clearly from colorless to pink around the level of 2 μg L−1 Hg2+, which just meets with the maximum residue level of Hg2+in drinking water recommended by U.S. EPA, so the water samples with Hg2+ concentration over 2 μg L−1could be selected rapidly by naked eye. Moreover, the quantification of Hg2+ could be obtained by fluorescence detection of test solution. The best extraction efficiency of Hg2+ by DLLLME could be obtained by using 200 mL water sample (pH 5.0, 50 °C), 150 μL extraction solvent (lauric acid, LA) and 3 mL dispersive solvent (methanol). Thus an enrichment factor of ∼407 and the limit of fluorescence detection of 0.03 μg L−1 could be achieved. The method was also highly selective for Hg2+ with tolerance to at least 1000-fold of the foreign metal ions. This method was successfully applied to detect Hg2+ in deionized water, tap water and sea water.
