title: A quantitative LC-MS/MS method for simultaneous determination of cocaine and its metabolites in whole blood.
abstract: As new metabolic pathways of cocaine were recently identified, a high performance liquid chromatography tandem mass spectrometry (LC-MS/MS) method was developed to simultaneously determine cocaine and nine cocaine-related metabolites in whole blood samples. One-step solid phase extraction was used to extract all of the ten compounds and corresponding internal standards from blood samples. All compounds and internal standards extracted were separated on an Atlantis T3 (100Å, 3μm, 2.1mm×150mm I.D) column and detected in positive ion and high sensitivity mode with multiple reaction monitoring. This method was validated for its sensitivity, linearity, specificity, accuracy, precision, recovery, and stability. All of the ten compounds were quantifiable ranging from the lower limit of quantification (LLOQs) of ∼10nM (1.9-3.2ng/ml) to ∼1000nM (190-320ng/ml) without any interfering substance. Accuracy and precision were determined, and both of them were within the acceptance criteria of the United States (US) Food and Drug Administration (FDA) and European Medicines Agency (EMA) guidelines. The recovery was above 66.7% for all compounds. Stability tests demonstrated the stability of compounds under different storage conditions in whole blood samples. The method was successfully applied to a pharmacokinetic study with co-administration of cocaine and alcohol in rats.
authors.affiliation: Molecular Modeling and Biopharmaceutical Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, United States.
authors.forename: Xiabin
authors.initials: X
authors.lastname: Chen
authors.affiliation: Molecular Modeling and Biopharmaceutical Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, United States.
authors.forename: Xirong
authors.initials: X
authors.lastname: Zheng
authors.affiliation: Molecular Modeling and Biopharmaceutical Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, United States.
authors.forename: Kai
authors.initials: K
authors.lastname: Ding
authors.affiliation: Molecular Modeling and Biopharmaceutical Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, United States.
authors.forename: Ziyuan
authors.initials: Z
authors.lastname: Zhou
authors.affiliation: Molecular Modeling and Biopharmaceutical Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, United States. Electronic address: zhan@uky.edu.
authors.forename: Chang-Guo
authors.initials: CG
authors.lastname: Zhan
authors.affiliation: Molecular Modeling and Biopharmaceutical Center, Department of Pharmaceutical Sciences, College of Pharmacy, University of Kentucky, 789 South Limestone Street, Lexington, KY 40536, United States. Electronic address: fzhen2@uky.edu.
authors.forename: Fang
authors.initials: F
authors.lastname: Zheng
mesh_terms: D000818:Animals; D002853:Chromatography, Liquid / Q000379:methods; D003042:Cocaine / Q000031:analogs & derivatives / Q000097:blood* / Q000378:metabolism; D006801:Humans; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: C008671:norcocaine; D003042:Cocaine
keywords: Alcohol; Cocaine; Drug metabolism; LC–MS/MS; SPE