title: Detection of clenbuterol at trace levels in doping analysis using different gas chromatographic-mass spectrometric techniques.
abstract: This study demonstrates the development of a gas chromatography-triple quadrupole tandem mass spectrometry (GC-MS-MS) assay to detect clenbuterol in human urine and the comparison of this method with GC-MS techniques and gas chromatography-high resolution mass spectrometry (GC-HRMS) techniques. Urine samples were hydrolyzed with β-glucuronidase, extracted with methyl tert-butyl ether and dried under nitrogen. The derivative reagent was N-methyl-N-(trimethylsilyl)-trifluoroacetamide with NH4I and was analyzed by GC-MS, GC-MS-MS and GC-HRMS. A validation study was conducted by GC-MS-MS. The analyses of clenbuterol using different mass spectrometric techniques were compared. The limit of detection (LOD) for clenbuterol in human urine was 2 ng/mL by GC-MS (selected ion monitoring mode: SIM mode), 0.06 ng/mL by GC-HRMS and 0.03 ng/mL by GC-MS-MS, respectively, while the LOD by GC-HRMS was 0.06. With GC-MS-MS, the intra-assay and inter-assay precisions were less than 15%, the recoveries were 86 to 112% and the linear range was 0.06 to 8.0 ng/mL. The GC-MS under SIM mode can be used as a screening tool to detect clenbuterol at trace levels in human urine. The GC-MS-MS and GC-HRMS methods can confirm clenbuterol when its concentration is below 2 ng/mL. The results demonstrate that the GC-MS-MS method is quite sensitive, specific and reliable for the detection of clenbuterol in doping analysis.
authors.affiliation: National Anti-doping Laboratory, China Anti-Doping Agency, 1st Anding Road, ChaoYang District, Beijing 100029, P. R. China. yangsheng@chinada.cn
authors.forename: Sheng
authors.initials: S
authors.lastname: Yang
authors.forename: Xin
authors.initials: X
authors.lastname: Liu
authors.forename: Yanyi
authors.initials: Y
authors.lastname: Xing
authors.forename: Dapeng
authors.initials: D
authors.lastname: Zhang
authors.forename: Shan
authors.initials: S
authors.lastname: Wang
authors.forename: Xiaobing
authors.initials: X
authors.lastname: Wang
authors.forename: Youxuan
authors.initials: Y
authors.lastname: Xu
authors.forename: Moutian
authors.initials: M
authors.lastname: Wu
authors.forename: Zhenwen
authors.initials: Z
authors.lastname: He
authors.forename: Jian
authors.initials: J
authors.lastname: Zhao
mesh_terms: D000318:Adrenergic beta-Agonists / Q000097:blood* / Q000652:urine*; D002849:Chromatography, Gas / Q000379:methods*; D002976:Clenbuterol / Q000097:blood* / Q000652:urine*; D004300:Doping in Sports / Q000517:prevention & control; D006801:Humans; D057230:Limit of Detection; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D000318:Adrenergic beta-Agonists; D002976:Clenbuterol