title: Direct determination of tamoxifen and its four major metabolites in plasma using coupled column high-performance liquid chromatography.
abstract: A rapid, rugged and fully automated method has been developed for the determination of tamoxifen and its major metabolites in plasma. The system is based upon an in-line extraction process combined with column switching to a coupled analytical column. The plasma sample is deproteinated by the addition of acetonitrile before injection onto a semi-permeable surface (SPS) cyano guard column (1.0 x 0.46 cm I.D.). After washing the guard column briefly with water, the sample is eluted with a mobile phase composed of 35% acetonitrile in 20 mM potassium phosphate buffer (pH 3). The eluent is directed through a cyano analytical column (25 x 0.46 cm I.D.) and a photochemical reactor where the analytes are converted to highly fluorescent phenanthrene derivatives. Tamoxifen, 4-hydroxytamoxifen, N-desdimethyltamoxifen, N-desmethyltamoxifen and tamoxifen-ol are eluted in that order at a flow-rate of 1.0 ml/min. The method has been validated for use in a clinical study utilizing tamoxifen in the treatment of recurrent cerebral astrocytomas.
authors.affiliation: McGill University, Department of Oncology, Montreal General Hospital, Que., Canada.
authors.forename: K M
authors.initials: KM
authors.lastname: Fried
authors.forename: I W
authors.initials: IW
authors.lastname: Wainer
mesh_terms: D000293:Adolescent; D000328:Adult; D002851:Chromatography, High Pressure Liquid / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D012680:Sensitivity and Specificity; D013629:Tamoxifen / Q000031:analogs & derivatives / Q000097:blood*
chemical_list: D013629:Tamoxifen; C016601:afimoxifene; C052626:ICI 142269; C049433:desdimethyltamoxifen; C028787:N-desmethyltamoxifen