Determination of Selenomethionine and Selenocysteine in Human Serum Using Speciated Isotope Dilution-Capillary HPLC-Inductively Coupled Plasma Collision Cell Mass Spectrometry. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Analytical Chemistry Année : 2004

Determination of Selenomethionine and Selenocysteine in Human Serum Using Speciated Isotope Dilution-Capillary HPLC-Inductively Coupled Plasma Collision Cell Mass Spectrometry.

Résumé

A method for the accurate detn. of selenoamino acids in human serum by HPLC-ICPMS was developed using the species-specific isotope diln. anal. principle. A serum sample was enzymically digested with a mixt. of lipase and protease after derivatization of the selenocysteine residues with iodoacetamide. The selenoamino acid fraction was isolated by size exclusion LC followed by the sepn. of selenomethionine and the carboxymethylated selenocysteine by capillary HPLC. The isotope-specific detn. of 77Se and 80Se was achieved online by ICP collision cell MS allowing the removal of polyat. interferences. Quantification was carried out by isotope diln. using a 77Se-labeled selenomethionine spike and the detn. of the 77Se/80Se ratio in the cHPLC selenomethionine peak. The accurately detd. selenomethionine was used as an internal std. for the selenocysteine detn. from the same chromatogram. The modification of the previously developed cHPLC-ICPMS interface allowed the redn. of the abs. detection limits twice (down to the 75-fg level), which resulted in the lowest ever reported procedural detection limits (below 0.5 ng g-1 for a 450-mg serum sample). The precision was less than 5% RSD. The method was validated by the mass balance of selenium (amino acid incorporated vs. total). [on SciFinder(R)]

Dates et versions

hal-01560726 , version 1 (11-07-2017)

Identifiants

Citer

Jorge Ruiz-Encinar, Dirk Schaumlöffel, Yasumitsu Ogra, Ryszard Lobinski. Determination of Selenomethionine and Selenocysteine in Human Serum Using Speciated Isotope Dilution-Capillary HPLC-Inductively Coupled Plasma Collision Cell Mass Spectrometry.. Analytical Chemistry, 2004, 76 (Copyright (C) 2017 American Chemical Society (ACS). All Rights Reserved.), pp.6635--6642. ⟨10.1021/ac049280h⟩. ⟨hal-01560726⟩
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