title: Determination of alpha-tocopherolquinone in human serum samples by liquid chromatography with fluorescence detection and on-line post-column derivatization.
abstract: A HPLC/fluorescence method with on-line post-column derivatization by a photoreactor was developed, where alpha-, beta + gamma- and delta-tocopherolquinone (TQ) are separated on a 250 mm x 4.6 mm RP-18 column. The LOD is about 250 pg for all TQs. In combination with a two-step sample preparation procedure, this method was successfully employed for measurement of alpha-TQ in human serum samples. Recovery for alpha-TQ from spiked serum was excellent (99 +/- 5%) and results of alpha-TQ determinations in 111 serum samples are reported. Additionally, possibilities for determination of other TQs in serum and alternative derivatization with a zinc reduction column are discussed.
authors.affiliation: Robert Koch-Institute, Pharmacoepidemiology, Seestr. 10, 13353 Berlin, Germany.
authors.forename: Dagmar
authors.initials: D
authors.lastname: Pollok
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Melchert
mesh_terms: D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid / Q000379:methods*; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D013050:Spectrometry, Fluorescence / Q000379:methods*; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000097:blood*
chemical_list: D014810:Vitamin E; C002421:tocopherylquinone