title: Simultaneous determination of thienorphine and its active metabolite thienorphine glucuronide in rat plasma by liquid chromatography-tandem mass spectrometry and its application to pharmacokinetic studies.
abstract: A simple, sensitive and reliable method was developed to determine simultaneously the concentrations of thienorphine and its metabolite thienorphine glucuronide conjugate in rat plasma by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The metabolite was identified by MS: thienorphine glucuronide conjugate. Sample preparation involved protein precipitation with methanol. Analytes were separated on Finnigan BetaBasic-18 column (150 mm x 2.1mm i.d., 5 microm) using methanol: water: formic acid (56:44:0.1, v/v/v) as mobile phase at a flow rate of 0.2 ml/min. The method had a linear calibration curve over the concentration range of 0.1-50 ng/ml for thienorphine and 2-1000 ng/ml for thienorphine glucuronide conjugate, respectively. LOQ of thienorphine and thienorphine glucuronide conjugate was 0.1 and 2 ng/ml, respectively. The intra- and inter-batch precisions were less than 12% and their recoveries were greater than 80%. Pharmacokinetic data of thienorphine and its metabolite thienorphine glucuronide conjugate obtained with this method following a single oral dose of 3mg/kg thienorphine to rats were also reported for the first time.
authors.affiliation: Key Laboratory of Drug Metabolism & Pharmacokinetics, Beijing Institute of Pharmacology and Toxicology, 27 Taiping Road, Beijing 100850, PR China.
authors.forename: Qi
authors.initials: Q
authors.lastname: Kong
authors.forename: Jianzhong
authors.initials: J
authors.lastname: Qiao
authors.forename: Xiaoying
authors.initials: X
authors.lastname: Wang
authors.forename: Shulan
authors.initials: S
authors.lastname: Yuan
authors.forename: Zhenqing
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zehui
authors.initials: Z
authors.lastname: Gong
authors.forename: Jinxiu
authors.initials: J
authors.lastname: Ruan
mesh_terms: D000818:Animals; D002047:Buprenorphine / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D002138:Calibration; D002853:Chromatography, Liquid / Q000379:methods*; D020719:Glucuronides / Q000097:blood* / Q000493:pharmacokinetics; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D020719:Glucuronides; C512397:thienorphine; D002047:Buprenorphine