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

摘要

A novel, robust hydride generation system compatible with sample introduction with inductively coupled plasma mass spectrometry is described and applied 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 mixing the acidified sample and the sodium borohydride reductant solution at the tip of a cross-flow nebuliser. A modified Scott spray chamber serves as a gas\u2013liquid separator, providing 30 s wash-in and wash-out times. Analytical results generated by external calibration and isotope dilution methodologies agree well with the certified values for Se in certified biological reference materials DORM-2 and DOLT-2. Detection limits for Se and other hydride forming elements, i.e., As, Sn and Sb, are below 10 ng l\u22121 with typical precision of 2% RSD at the 10 ng ml\u22121 level. Volatile species of Cu, Rh, Pd, Ag, In, Au, Hg, Tl and Pb are also produced, and estimated sensitivities and detection limits for these elements are reported.