Amendola Luca, Colamonici Cristiana, Rossi Francesca, Botrè Francesco
Laboratorio Antidoping, Federazione Medico Sportiva Italiana, Largo Giulio Onesti 1, 00197, Rome, Italy.
J Chromatogr B Analyt Technol Biomed Life Sci. 2002 Jun 15;773(1):7-16. doi: 10.1016/s1570-0232(02)00141-1.
This work presents a GC-MS-MS-MS method for the direct determination of clenbuterol in human urine. The method comprises a pretreatment procedure and the instrumental analysis of the derivatives performed by GC-MS(3) (ion trap) with electron impact ionization. The GC-MS(3) analysis allows isolation and characterization of specific fragments from the original (MS(1)) molecular structure, and in particular, those fragments originating from the precursor ion cluster (m/z=335-337) characteristic of clenbuterol. The MS(2) product fragment m/z=300 is in turn used as a further precursor fragment giving rise to a MS(3) spectrum specific for clenbuterol. MS(4) fragmentation spectra were also investigated. However, further fragmentation of MS(3) product ions does not lead to functional MS(4) spectra nor to any significant increase in the signal-to-noise ratio. The sensitivity limit of the MS(3) technique is lower than 0.2 microg/l, with a linear range between 0.5 and 5 microg/l, thus matching the basic requirements for antidoping analysis according to the guidelines of the International Olympic Committee. Due to its overall analytical performance, the method is presently being evaluated as a confirmation protocol to be followed to detect illicit clenbuterol administration to the athletes, and compared with reference GC-MS and GC-MS-MS techniques.
本研究提出了一种用于直接测定人尿中克伦特罗的气相色谱-串联质谱-串联质谱法。该方法包括预处理程序以及采用电子轰击电离的气相色谱-串联质谱（离子阱）对衍生物进行仪器分析。气相色谱-串联质谱分析能够从原始（一级质谱）分子结构中分离并鉴定特定碎片，特别是那些源自克伦特罗特征性前体离子簇（质荷比=335 - 337）的碎片。二级质谱产物碎片质荷比=300进而用作进一步的前体碎片，产生克伦特罗特有的三级质谱图。还对四级质谱裂解图谱进行了研究。然而，三级质谱产物离子的进一步裂解既不会产生有效的四级质谱图，也不会使信噪比有任何显著提高。三级质谱技术的灵敏度极限低于0.2微克/升，线性范围在0.5至5微克/升之间，从而符合国际奥委会指南中反兴奋剂分析的基本要求。鉴于其整体分析性能，该方法目前正作为检测运动员非法使用克伦特罗的确认方案进行评估，并与参考气相色谱-质谱和气相色谱-串联质谱技术进行比较。
