ABSTRACT
ICP-MS has gained popularity over the years, mainly because of its ability to rapidly quantitate ultratrace metal contamination levels. However, in its basic design, ICP-MS cannot reveal anything about the metal’s oxidation state, alkylated form, how it is bound to a biomolecule, or how it interacts at the cellular level. The desire to understand in what form or species an element exists led researchers to investigate the combination of chromatographic separation devices with ICP-MS. The ICP mass spectrometer becomes a very sensitive detector for trace element speciation studies when coupled to a chromatographic separation device based on HPLC, ion chromatography (IC), gas chromatography (GC), size exclusion chromatography (SEC), capillary electrophoresis (CE), etc. In these hyphenated techniques, elemental species are separated based on their chromatographic retention, mobility, or molecular size, and then eluted/passed into the ICP mass spectrometer for detection.1 The intensities of the eluted peaks are then displayed for each isotopic mass of interest, in the time domain, as shown in Figure 18.1. The figure shows a typical time-resolved chromatogram for a selected group of masses.
