CAPILLARY ELECTROPHORESIS INDUCTIVELY-COUPLED PLASMA SPECTROMETRY FORRAPID ELEMENTAL SPECIATION

Initial results using the combination of capillary electrophoresis (CE ) and sensitive, element-selective, inductively coupled plasma (ICP) o ptical emission spectrometry (OES) and mass spectrometry (RIS) for rap id elemental speciation are reported. An interface to produce a fine a erosol that is efficiently transported from the end of the electrophor esis capillary to the ICP with negligible liquid dead volume was devel oped, By using element-selective detection provided by ICP spectrometr y, electrophoretic resolution could be traded off for rapid analysis t imes, CE-ICP spectrometry was used for elemental speciation of inorgan ic ions with different charge states, organometallic species, and meta l-ligand complexes. CE-ICP spectrometry may also be useful to rapidly determine metal-ligand complex stability constants, Analysis times wer e generally less than 2 min. Detection limits for CE/ICP-OES were with in a factor of 19 of those typically obtained using ICP-OES for elemen tal analysis (without speciation). Detection limits for CE/ICP-MS were generally a factor of 60 times higher than those typically obtained b y using ICP-MS for elemental analysis (without speciation), However, t he detection limits for CE/ICP-MS were as low as 0.06 ppb, which corre sponds to 8 fg (90 amol) of Sr in the injected sample, Peak area and e lution time reproducibility were typically better than 3% relative sta ndard deviation for successive injections.