Speciation of inorganic selenium by inductively coupled plasma mass spectrometry with hydraulic high pressure nebulization

The speciation of Se-IV and Se-VI was studied by using hydraulic high pressure nebulization for sample introduction in inductively coupled plasma mass spectrometry. Ion-pair chromatography with a reversed-phase column was applied using tetrabutylammonium acetate as reagent and a methanol-water mixture as eluent. Operational conditions were carefully optimized. With a 200 mu l sample loop for injection, detection limits of 0.14 mu g 1(-1) were realized, whereas with an injection volume of 2 ml detection limits could be improved to 16 ng 1(-1). Application of the method is demonstrated by the analysis of a tap water sample.