In situ hydride generation for multielement analysis in complex matrices through ICP-MS with a high-temperature sample introduction system

Hydride generation (HG) remains a powerful sample introduction strategy for the determination of some elements by inductively coupled plasma mass spectrometry (ICP-MS). In this study, two HG-based configurations were systematically evaluated, including a conventional HG system with external gas-liquid separation and a structurally modified high-temperature torch-integrated sample introduction system (hTISIS). The hTISIS was equipped with an auxiliary inlet, i.e., drain tube, for the introduction of NaBH 4 and HCl, allowing gas-liquid reaction and phase separation to occur directly within the thermostated spray chamber. This latter setup, HG-hTISIS, was employed under three different modes: sample introduction through both the nebulizer and the drain tube (mode 1); sample introduction only through nebulization (mode 2); and sample introduction only through the drain tube (mode 3). In all three instances, hydride-forming reagents were continuously delivered by means of the drain tube. The operability of all configurations was assessed for five hydride-forming elements (As, Se, Sb, Sn, Bi), while quantitative performance was ultimately established using the optimized in situ HG-hTISIS configuration operated at 200 °C. Non-hydride-forming elements including Li, Al, Mn, Ti, Co, V, Cr, Ni, Cu, Zn, Rb, Sr, Ag, Ba, Cd, Tl, and Pb were also determined under this configuration, with an efficient aerosol transport enabled by the thermal chamber. A Box-Behnken design was employed to optimize the concentrations of NaOH, NaBH 4 , and HCl, ensuring robust hydride formation and minimal matrix effects across a wide range of conditions. Analytical performance was evaluated in terms of sensitivity, precision, and limits of detection (LODs). Signal enhancement factors ranging from 13 to 150 were achieved for hydride-forming elements, with sub-μg L −1 detection limits and a sample uptake of only 30 μL min −1 , in contrast to 0.5 mL min −1 in the conventional HG system. Moreover, foam formation was significantly mitigated in biological matrices, allowing direct analysis after sample dilution. Accuracy was confirmed through the analysis of certified reference materials of environmental and clinical origin, showing good agreement with the certified values. These results highlighted the analytical potential of the hydride generation HG-hTISIS configuration as a sensitive, low-consumption, and multielement-compatible alternative for the analysis of complex matrices by ICP-MS. • A modified high-temperature torch integrated system has been adapted for hydride generation ICP-MS analysis. • Hydride and non-hydride generation elements have been determined in clinical and environmental CRMs through the HG-hTISIS. • The HG-hTISIS provides low enough limits of detection and accurate results for CRMs.