HYPHENATION OF CAPILLARY ELECTROPHORESIS TO INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY AS AN ELEMENT-SPECIFIC DETECTION METHOD FOR METAL SPECIATION

A stepwise development for the use of capillary electrophoresis and in ductively coupled plasma mass spectrometry (ICP-MS) for speciation inv estigations is presented. The high resolution power of CE is used for the separation of metal species, whereas ICP-MS is taken for element-s pecific detection with low detection limits. This contribution starts with an off-line combination of both instruments. Separation and ident ification of species in model solutions and real samples are shown by scanning UV detection at the CE unit with subsequent metal quantificat ion in peak related fractions, applying electrothermal vaporization IC P-MS. Finally, first separations are demonstrated, using the on-line h yphenation with a laboratory-made nebulizer. Here, standard solutions are separated and monitored by UV and ICP-MS. Stability of electrical current during nebulization was checked and a possibly interfering suc tion flow was estimated. After optimization sufficient electropherogra ms were obtained. Advantages and problems are discussed for both modes .