Determination of serum or plasma alpha-tocopherol by high performance liquid chromatography: optimization of operative models

• Published in: Annales de biologie clinique (Paris) Vol. 53; no. 6; p. 343
• Main Authors: Jezequel-Cuer, M, Le Moël, G, Mounié, J, Peynet, J, Le Bizec, C, Vernet, M H, Artur, Y, Laschi-Loquerie, A, Troupel, S
• Format: Journal Article
• Language: French
• Published: France 1995
• Subjects: Chromatography, High Pressure Liquid - methods; Chromatography, High Pressure Liquid - standards; Humans; Solvents; Vitamin E - blood
• ISSN: 0003-3898; 1950-6112

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.