title: Determination by liquid chromatography-mass spectrometry of clomiphene isomers in the plasma of patients undergoing treatment for the induction of ovulation.
abstract: A rapid, sensitive and selective LC-MS method is described for the simultaneous determination of zuclomiphene and enclomiphene in plasma from patients undergoing treatment with clomiphene citrate for the induction of ovulation. Samples spiked with N-didesmethyltamoxifen, the internal standard, were extracted into methyl tertiary butyl ether. The compounds were separated on a Luna C(18) analytical column, and a mobile phase of methanol-water (70:30 v/v) containing 0.05% trifluoroacetic acid at a flow rate of 1ml/min. The limits of determination were 35pg/ml and 7pg/ml for zu- and enclomiphene, respectively. Within-day coefficients of variation ranged from 2.1% to 7.2%.
authors.affiliation: Academic Unit of Clinical Pharmacology, University of Sheffield, Royal Hallamshire Hospital, Sheffield, UK.
authors.forename: H K
authors.initials: HK
authors.lastname: Crewe
authors.forename: C
authors.initials: C
authors.lastname: Ghobadi
authors.forename: A
authors.initials: A
authors.lastname: Gregory
authors.forename: A
authors.initials: A
authors.lastname: Rostami-Hodjegan
authors.forename: M S
authors.initials: MS
authors.lastname: Lennard
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D002996:Clomiphene / Q000097:blood / Q000737:chemistry / Q000494:pharmacology*; D064695:Enclomiphene; D005260:Female; D006801:Humans; D013058:Mass Spectrometry / Q000379:methods*; D015394:Molecular Structure; D010060:Ovulation / Q000187:drug effects*; D015203:Reproducibility of Results
chemical_list: D002996:Clomiphene; D064695:Enclomiphene