MULTIELEMENT DETERMINATION OF TRACE-ELEMENTS IN SEDIMENT SAMPLE BY INDUCTIVELY-COUPLED PLASMA-MASS SPECTROMETRY WITH MICROSAMPLING TECHNIQUE

A discrete microsampling technique for multielement determination of t race elements by inductively coupled plasma mass spectrometry has been investigated for analyses of samples containing large amounts of matr ix elements. In the technique, 100 mu l of the sample solution was int roduced into the plasma by using a six-way valve, and 10 elements were detected in peak hopping mode during a single mass range scan. As a r esult, a transient peak profile of the signal for each element was obs erved at each m/z position. The peak area measurement method was estab lished for the quantitative analysis. The optimization of instrumental conditions and matrix effects in multielement determination were inve stigated in detail. The discrete microsampling technique was found to reduce some memory effects due to matrices in ICP-MS. The present syst em was applied to the analyses of standard sediment sample and 30 elem ents at the mu g g(-1) level were successfully determined without matr ix separation.