Coupling of nitric acid digestion and anion-exchange resin separation for the determination of methylmercury isotopic composition within organisms

Atomic spectrometry update: review of advances in elemental speciation

“…The rst of these presents a method combining acidic leaching and batch AEC for selectively extracting MeHg from sh and aquatic invertebrates prior to Hg isotope ratio measurements. 91 The rst step involves 30% HNO 3 at 60 °C for 12 hours which is followed by a two stage extraction, each of 2 hours duration, with Bio-Rad AG 1-X4 resin and HCl, to adsorb negatively charged iHg species, e.g., HgCl 3 − and HgCl 4 2− , with neutral MeHg species, e.g. MeHgCl, remaining in solution for oxidation with BrCl followed by reduction of the Hg 2+ formed to Hg 0 and then a purge and trap step prior to analysis with MC-ICP-MS.…”