title: Determination of the Metabolite of Ephedrine, 4-Hydroxyephedrine, by LC-MS-MS in Rat Urine and Its Application in Excretion Profiles After Oral Administration of Ephedra sinica Stapf and Processing Ephedra sinica Stapf.
abstract: This study aims to study the changes of metabolism of Ephedra sinica Stapf caused by processing. A sensitive and rapid high-performance liquid chromatographic tandem mass spectrometry (LC-MS-MS) method was developed for the quantitation of the major metabolite of ephedrine, 4-hydroxyephedrine, utilizing lidocaine as the internal standard in rat urine. Urine samples were precipitated with acetonitrile. Chromatographic separation was achieved on an Ultimate C18 analytical column. Detection was performed by a multiple reaction monitoring mode via an electrospray ionization source operating in the positive ionization mode. The method was linear over the concentration range of 0.05-1.0c for all components. The intra- and inter-day precision values were <13.2% and the deviations ranged from -8.4% to 7.5%. The recoveries at three levels were more than 66.2%. The fully validated method was used to study the pharmacokinetic profile of 4-hydroxyephedrine in rat urine to investigate the effects caused by processing.
authors.affiliation: Department of Foreign Languages, Chaohu University, Chaohu 238000, P.R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Xu
authors.affiliation: College of Pharmacy, Liaoning University, 66 Chongshan Road (M), Shenyang 110036, P.R. China yrchn@163.com.
authors.forename: Rui
authors.initials: R
authors.lastname: Yan
mesh_terms: D000284:Administration, Oral; D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods*; D004365:Drugs, Chinese Herbal / Q000008:administration & dosage* / Q000493:pharmacokinetics; D029790:Ephedra sinica; D004809:Ephedrine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000493:pharmacokinetics / Q000652:urine; D016014:Linear Models; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D004365:Drugs, Chinese Herbal; C026055:oxilofrine; D004809:Ephedrine