title: Quantitative determination of small selenium species in human serum by HPLC/ICPMS following a protein-removal, pre-concentration procedure.
abstract: Protein precipitation was incorporated into a sample preparation method for the quantitative determination of small "non-protein" selenium species in human serum by high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC/ICPMS). The advantages of cleaner matrix and concomitant concentration of the small compounds result in quantification limits in the native serum at the sub-micrograms Se per litre level. Spiking experiments with methyl 2-acetamido-2-deoxy-1-seleno-β-D-galactopyranoside (selenosugar 1), trimethylselenonium ion, selenomethionine, methylselenocysteine (MeSeCys) and selenate yielded recoveries from 73% to 103%. Selenite had a low recovery (44%), possibly owing to protein binding. The validated method was applied to serum samples from two volunteers before and after ingestion of a selenium food supplement. HPLC/ICPMS analysis showed, besides ingested selenate, the presence of selenosugar 1 and trace amounts of MeSeCys and methyl 2-amino-2-deoxy-1-seleno-β-D-galactopyranoside, which have not been reported in human serum before.
authors.affiliation: Institute of Chemistry-Analytical Chemistry, Karl-Franzens-University, Graz, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Kokarnig
authors.forename: Doris
authors.initials: D
authors.lastname: Kuehnelt
authors.forename: Michael
authors.initials: M
authors.lastname: Stiboller
authors.forename: Ulrike
authors.initials: U
authors.lastname: Hartleb
authors.forename: Kevin A
authors.initials: KA
authors.lastname: Francesconi
mesh_terms: D000328:Adult; D002851:Chromatography, High Pressure Liquid; D019587:Dietary Supplements; D005260:Female; D006801:Humans; D008297:Male; D016566:Organoselenium Compounds / Q000097:blood*; D011506:Proteins / Q000302:isolation & purification; D012643:Selenium / Q000008:administration & dosage / Q000097:blood; D021241:Spectrometry, Mass, Electrospray Ionization
chemical_list: D016566:Organoselenium Compounds; D011506:Proteins; D012643:Selenium