Determination of inorganic selenium speciation in waters by ion chromatography-inductively coupled plasma-mass spectrometry using eluant elimination with a membrane suppressor

Citation
D. Wallschlager et R. Roehl, Determination of inorganic selenium speciation in waters by ion chromatography-inductively coupled plasma-mass spectrometry using eluant elimination with a membrane suppressor, J ANAL ATOM, 16(9), 2001, pp. 922-925
Citations number
12
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
JOURNAL OF ANALYTICAL ATOMIC SPECTROMETRY
ISSN journal
0267-9477 → ACNP
Volume
16
Issue
9
Year of publication
2001
Pages
922 - 925
Database
ISI
SICI code
0267-9477(200109)16:9<922:DOISSI>2.0.ZU;2-7
Abstract
Selenium speciation in waters is performed by ion chromatography coupled to inductively Coupled plasma mass spectrometry (IC-ICP-MS). Selenite, selena te and selenocyanate [Se(IV). Se(VI) and SeCN] are separated with a step gr adient elution using dilute NaOH as the eluant. After the separation, the e luant is converted to water on-line by a membrane self-regenerating suppres sor, and then introduced into the nebulizer. It is shown that the eliminati on of the NaOH matrix improves analytical performance and instrument Stabil ity. From 1 mL sample, detection limits (as 3 sigma of the baseline noise) of 2.5, 1.6 and 2.6 ng L-1 are achieved for Se(IV), Se(VI) and SeCN, respec tively, if 2% methanol is added to the eluant. Reproducibility of the metho d was 7.6 10.5% for the three species at the 50 ng L-1 level and 0.4-7.4% a t the 500 ng L-1 level. The method was validated with SRM 1643d (NIST). The analytical performance for the three isotopes Se-77, Se-78 and Se-82 is co mpared under various plasma conditions, and Se-82 is identified as the Most Suitable isotope yielding the lowest detection limits under any conditions . As a demonstration of the method's detection power. it is Successfully ap plied to determine Se speciation in an estuarine water.