Analytical Strategy for the Determination of Selenium in Biological Materials by Inductively Coupled Plasma-Mass Spectrometry with a Dynamic Reaction Cell

作者：Wieczorek Marcin^*; Tobiasz Anna; Dudek Adamska Danuta; Walas Stanislaw; Koscielniak Pawel

来源：Analytical Letters, 2017, 50(14): 2279-2291.

DOI：10.1080/00032719.2016.1273361

• Dynamic reaction cell
• inductively coupled plasma-mass spectrometry
• internal standard
• set of standards method
• standard addition method

Selenium was determined in serum, hair, and tobacco by inductively coupled plasma-mass spectrometry using Se-77, Se-78, and Se-82. The set of standards method (SSM) and the standard addition method (SAM) were applied to calibration with and without the use of internal standards (Ge-72 and Rh-103). In addition, the usefulness of the dynamic reaction cell (DRC) with methane as the reaction gas was characterized. The results obtained in different conditions were evaluated in terms of precision and accuracy. It was demonstrated theoretically and experimentally that an internal standard is a potential source of systematic errors as it can be influenced multiplicatively and additively by its own interferents (independently of selenium). Furthermore, it was shown thatagainst common opinionan internal standard can fail in elimination of chemical interference effects influencing selenium and in increasing of precision of selenium determinations. The DRC was shown to be effective in the elimination of additive effects, although the results obtained by both SSM and SAM with DRC were systematically positively erroneous. Finally, selenium was determined accurately in each examined sample when SAM was applied to calibration, and signals were measured either for Se-82 without the use of the DRC, or for Se-77 or Se-78 with the use of the DRC. In addition, it has also been shown that samples should be diluted prior to analysis to the greatest acceptable extent.

• 出版日期2017