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A systematic study on the high-temperature Torch Integrated Sample Introduction System (TISIS) for use in Inductively Coupled Plasma Mass Spectrometry (ICP-MS) has been performed. The investigation included the optimization of the relevant parameters (chamber temperature, sheathing gas flow rate, nebulizer gas flow rate, sample uptake rate), the evaluation of its performance characteristics (sensitivity, limits of detection, stability, memory effects, use with the dynamic reaction cell) and representative applications to environmental, biological and clinical samples. Under the optimal conditions (T=150°C; nebulizer gas flow rate of 0.7Lmin(-1) along with sheathing gas flow rate of 0.35Lmin(-1) and a sample uptake rate of 20μLmin(-1)), the sensitivity was from 2 to 8 times higher than that measured using a conventional micronebulizer/mini-spray chamber system, due to the enhanced analyte mass transport toward the plasma and the solvent introduction in the vapour form. In addition, for several elements, TISIS provided lower limits of detection than the conventional system, even when the latter worked at 5-fold higher sample uptake rate. Short-term and long-term precision was better than 5%. Spectroscopic interferences arising from common matrices were efficiently removed by the dynamic reaction cell technique. The application of TISIS/ICP-MS to representative certified reference samples (spinach leaves, marine plankton, bone tissue, human blood) proved the suitability of this system for the accurate analysis of limited-size samples., (Copyright © 2013 Elsevier B.V. All rights reserved.)

A method for the determination of ultratrace amounts of Cr, Fe, Mn, Pb and Zn in seawater has been developed. It combined the low-blank magnesium hydroxide coprecipitation procedure with quadrupole inductively coupled plasma mass spectrometry and used the dynamic reaction cell technique to resolve the polyatomic interferences arising from the residual matrix, the solvent and plasma gases. Detection limits (3σ(B), n=10) for Cr, Fe, Mn, Pb and Zn were 0.02, 0.10, 0.01, 0.002 and 0.19 nM, respectively, using 50 mL of seawater sample. The accuracy of the analytical procedure was verified by the analysis of the seawater reference materials CASS-4, NASS-5, SAFe D2 and SAFe S. The analytical precision ranged from 3% to 16% (n=6), with a sample throughput of about 6 samples h(-1)., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Inductively coupled plasma quadrupole mass spectrometry (ICP-QMS), ICP sector field mass spectrometry (ICP-SFMS) and ICP atomic emission spectrometry (ICP-AES) were compared with regard to the direct determination of rare earth elements (REEs) in geological samples. In order to reduce the polyatomic interferences occurring in ICP-QMS, the use of a cooled spray chamber was optimized, obtaining a significant decrease of the oxide ions formation (about 50%) and a consequent mitigation of the interfering effects. Precision and accuracy of the method were demonstrated by the analyses of sediment and soil certified reference materials. ICP-SFMS working in high-resolution mode also provided accurate results, with similar precision to ICP-QMS (RSD%: 3-8%) and comparable or better limits of detection. Quantification limits of the procedures were 18-52 ng g(-1) and 10-780 ng g(-1) for sector field- and quadrupole-ICP-MS, respectively. Accurate and precise determination of most REEs was also achieved by ICP-AES using both pneumatic and ultrasonic nebulization, after a careful selection of the emission lines and compensation for non-spectral interferences by internal standardization. The three techniques were finally applied to glaciomarine sediment samples collected in Antarctica, providing comparable analytical data on REE abundance and depth pattern., (Copyright © 2010 Elsevier B.V. All rights reserved.)