A novel introduction system for hydride generation-inductively coupled plasma mass spectrometry: determination of selenium in biological materials

A novel, robust hydride generation system compatible with sample introducti on with inductively coupled plasma mass. spectrometry is described and appl ied to the determination of Se in biological tissues. A short reaction time (60 ms) and a rapid separation of the reaction products is obtained by mix ing the acidified sample and the sodium borohydride reductant solution at t he tip of a cross-flow nebuliser. A modified Scott spray chamber serves as a gas-liquid separator, providing 30 s wash-in and wash-out times. Analytic al results generated by external calibration and isotope dilution methodolo gies agree well with the certified values for Se in certified biological re ference materials DORM-2 and DOLT-2. Detection limits for Se and other hydr ide forming elements, i.e., As, Sn and Sb, are below 10 ng l(-1) with typic al precision of 2% RSD at the 19 ng ml(-1) level. Volatile species of Cu, R h, Pd, Ag, In, Au,Hg, Tl and Pb are also produced, and estimated sensitivit ies and detection limits for these elements are reported.