ICP-MS for specific detection in capillary electrophoresis

The advantages of capillary electrophoresis (CE) as a powerful separation technique can be combined with the atomic specificity, multi-elemental character and extremely high sensitivity of an inductively coupled plasma mass spectrometry (ICP-MS) detector for metal-speciation studies in different fields of interest. However, the coupling of both commercially available instruments deserves particular attention if separative resolution, high analyte transport efficiency and sensitive detection are to be achieved. In that technical vein, the interface itself may be considered as the “key to success”. We review the different ways of performing CE-ICP-MS coupling so far and discuss interfaces based on conventional, micronebulizers and the generation of volatile species of analytes. We pay particular attention to those contributions aimed at improving the sensitivity achieved in CE-ICP-MS couplings. Finally, we review the latest applications (as reported from 2002 to June 2004) of CE-ICP-MS to tackle trace-element-speciation problems. It appears that initial technical problems for coupling CE to ICP-MS have now been overcome, so we expect an increasing number of applications of the technique in the field of trace-element speciation in the near future.