University of Pennsylvania, School of Veterinary Medicine, Department of Clinical Studies, New Bolton Center Campus, Kennett Square, PA, 19348, USA.
PA Equine Toxicology & Research Laboratory, 220 East Rosedale Avenue, West Chester, PA, 19382, USA.
Drug Test Anal. 2019 Mar;11(3):441-454. doi: 10.1002/dta.2516. Epub 2018 Nov 8.
A hydrophilic interaction liquid chromatography-tandem mass spectrometry method (HILIC-MS/MS) was developed for the simultaneous determination of 28 amphetamine-type stimulants (ATSs) in equine plasma for doping control analysis. In this method, stimulants were recovered from equine plasma by liquid-liquid extraction (LLE) at pH 9.5 using methyl tert-butyl ether and detected on a Thermo Finnigan triple quadrupole mass spectrometer operating in positive-ion mode electrospray ionization. All stimulants were eluted within 7 minutes and baseline separation was achieved for isomeric and isobaric compounds using HILIC chromatography. Extraction efficiency was greater than 80% and matrix effect was acceptable for most stimulants. The limit of detection (LOD) was in the range of 10-50 pg/mL and the lower limit of quantification (LLOQ) was in the range of 50-100 pg/mL. Quadratic regression was employed for quantification and the dynamic range of quantification was 50-10000 pg/mL. Confirmatory analysis criteria were established using product ion ratios and retention time. The limit of confirmation (LOC) was in the range of 20-100 pg/mL. Stability study results indicated that some stimulants were unstable in equine plasma at room temperature and 4°C. However, all the stimulants studied were stable at -20°C and - 80°C for the 6 month study period.
建立了一种亲水作用色谱-串联质谱法（HILIC-MS/MS），用于同时检测马血浆中的 28 种苯丙胺类兴奋剂（ATSs），以进行兴奋剂检测分析。在该方法中，通过在 pH 9.5 下使用甲基叔丁基醚进行液-液萃取（LLE）从马血浆中回收兴奋剂，并在正离子模式电喷雾电离的 Thermo Finnigan 三重四极杆质谱仪上进行检测。所有兴奋剂在 7 分钟内洗脱，使用 HILIC 色谱实现了异构体和等质量化合物的基线分离。萃取效率大于 80%，大多数兴奋剂的基质效应可接受。检测限（LOD）范围为 10-50pg/mL，定量下限（LLOQ）范围为 50-100pg/mL。采用二次回归进行定量，定量范围为 50-10000pg/mL。使用产物离子比和保留时间建立了确证分析标准。确证限（LOC）范围为 20-100pg/mL。稳定性研究结果表明，一些兴奋剂在室温下和 4°C 时在马血浆中不稳定。然而，在所研究的所有兴奋剂在-20°C 和-80°C 下在 6 个月的研究期间是稳定的。
