Palladium(II), Magnesium(II), and Barium(II) Nitrate Combinations for Matrix Modification in Electrothermal Atomic Absorption Measurement of Total Selenium in Human Urine

• Published in: Analytical biochemistry Vol. 220; no. 2; pp. 336 - 339
• Main Authors: Drake, E.N., Hain, T.D.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.08.1994
• Subjects: Adult; Barium Compounds; Female; Humans; Indicators and Reagents; Magnesium Compounds; Male; Nitrates; Palladium; Reference Values; Selenium - urine; Sensitivity and Specificity; Sex Characteristics; Spectrophotometry, Atomic - methods
• ISSN: 0003-2697; 1096-0309
• DOI: 10.1006/abio.1994.1346

Electrothermal atomic absorption spectrometry with a temperature-stabilizing platform and palladium(II) nitrate-magnesium nitrate-barium nitrate matrix modifier combination was used to measure total selenium concentrations in 0.5-ml samples of human urine. The method was validated by analysis of desiccated, standard urine samples (SRM 2670) from NIST. The peak height response was linear from 0 to 150 μg Se/liter urine with a sensitivity of 0.001 absorbance unit/μg Se/liter and a detection limit of 6 μg Se/liter (P = 0.05) for a single measurement. Total urinary selenium concentrations and urine volumes of 24-h samples from 28 healthy adult subjects on self-selected diets and living in San Angelo, Texas were measured. Daily total urinary excretions of 16 male and 12 female subjects (mean ± SD) were 28 ± 26 and 34 ± 25 μg Se/day, respectively. A single subject taking 300 μg Se/day in the form of aqueous SeO2 as a dietary supplement excreted 232 μg Se/day. The unsupplemented subjects′ daily selenium excretions correspond to a mean dietary intake of approximately 60 μg/day.