title: [Determination of serum or plasma alpha-tocopherol by high performance liquid chromatography: optimization of operative models].
abstract: A previous multicentric study set up by the Société française de biologie clinique has emphasized the usefulness of a standardized procedure for the determination by high performance liquid chromatography of alpha-tocopherol in serum or plasma. In our study, we have tested every step of the different published procedures: internal standard adduct, lipoprotein denaturation and vitamin extraction. Reproducibility of results was improved by the use of tocol as an internal standard when compared to retinol or alpha-tocopherol acetates. Lipoprotein denaturation was more efficient with ethanol addition than with methanol and when the ethanol/water ratio was > or = 0.7. Use of n-hexane or n-heptane gave the same recovery of alpha-tocopherol. When organic solvent/water ratio was > or = 1, n-hexane enabled to efficiently extract, in a one-step procedure, the alpha-tocopherol from both normo and hyperlipidemic sera. Performances of the selected procedure were: detection limit: 0.5 microM--linear range: 750 microM--within run coefficient of variation: 2.03%--day to day: 4.76%. Finally, this pluricentric study allows us to propose an optimised procedure for the determination of alpha-tocopherol in serum or plasma.
authors.affiliation: Laboratoire de biochimie A, hôpital Bichat, Paris, France.
authors.forename: M
authors.initials: M
authors.lastname: Jezequel-Cuer
authors.forename: G
authors.initials: G
authors.lastname: Le Moël
authors.forename: J
authors.initials: J
authors.lastname: Mounié
authors.forename: J
authors.initials: J
authors.lastname: Peynet
authors.forename: C
authors.initials: C
authors.lastname: Le Bizec
authors.forename: M H
authors.initials: MH
authors.lastname: Vernet
authors.forename: Y
authors.initials: Y
authors.lastname: Artur
authors.forename: A
authors.initials: A
authors.lastname: Laschi-Loquerie
authors.forename: S
authors.initials: S
authors.lastname: Troupel
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000592:standards; D006801:Humans; D012997:Solvents; D014810:Vitamin E / Q000097:blood*
chemical_list: D012997:Solvents; D014810:Vitamin E
vernacular_title: Dosage de l'alpha-tocophérol sérique ou plasmatique par chromatographie liquide haute performance: optimisation du mode opératoire.