title: Development and validation of a liquid chromatography-tandem mass spectrometry assay for determination of raloxifene and its metabolites in human plasma.
abstract: This paper describes the development and validation of a method for the detection of raloxifene (Ral) and its two glucuronide metabolites, raloxifene-6-glucuronide (M1) and raloxifene-4'-glucuronide (M2), in human plasma samples. Both glucuronides were synthesized enzymatically, purified and used as authentic standards. The assay involves a simple solid phase extraction (SPE) procedure of 0.5 mL of human plasma and subsequent analysis by LC-MS-MS. The recoveries were higher than 71% and chromatographic separation of all the analytes was accomplished in less than 7 min. Linear ranges (r(2)>0.99) were found from 0.200 to 340 microg/L, from 1.600 to 2720 microg/L and from 0.088 to 60.00 microg/L, for M1, M2 and Ral, respectively. The limits of detection achieved were 8, 11 and 6 ng/L for M1, M2 and Ral, respectively. The method presented was successfully applied to a genetic polymorphism study of 47 plasma samples from women taking Evista (raloxifene hydrochloride).
authors.affiliation: Faculty of Pharmacy, University of Ljubljana, Askerceva 7, Ljubljana, Slovenia. jurij.trontelj@ffa.uni-lj.si
authors.forename: Jurij
authors.initials: J
authors.lastname: Trontelj
authors.forename: Marija
authors.initials: M
authors.lastname: Bogataj
authors.forename: Janja
authors.initials: J
authors.lastname: Marc
authors.forename: Ales
authors.initials: A
authors.lastname: Mrhar
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D005260:Female; D014453:Glucuronosyltransferase / Q000378:metabolism; D006801:Humans; D020849:Raloxifene Hydrochloride / Q000097:blood* / Q000302:isolation & purification / Q000378:metabolism; D015203:Reproducibility of Results; D020845:Selective Estrogen Receptor Modulators / Q000097:blood* / Q000302:isolation & purification / Q000378:metabolism; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D020845:Selective Estrogen Receptor Modulators; D020849:Raloxifene Hydrochloride; D014453:Glucuronosyltransferase