High‐throughput doping control analysis of 28 amphetamine‐type stimulants in equine plasma using hydrophilic interaction liquid chromatography–tandem mass spectrometry. Issue 3 (8th November 2018)

• Record Type: Journal Article
• Authors: You, Youwen; Guan, Fuyu; D'Ippolito, Robert; Li, Xiaoqing; Soma, Lawrence R.; Robinson, Mary A.
• Is Part Of: Drug testing and analysis. Volume 11:Issue 3(2019)
• Page Start: 441
• Page End: 454
• Publication Date: 2018-11-08
• Subjects: Doping control -- Equine plasma -- HILIC‐MS/MS -- Racehorse -- Stimulants; Drugs -- Analysis -- Periodicals; Drug testing -- Periodicals; Chemistry, Forensic -- Periodicals; 615.1901
• DOI: 10.1002/dta.2516
• Languages: English
• ISSNs: 1942-7603

Abstract

Abstract: 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. Abstract : Stimulants are banned doping substances by the Association of Racing Commissioners International (ARCI) and the Fédération Équestre Internationale (FEI). To enforce the ban of stimulants in equine sports, a sensitive and high‐throughput HILIC–MS/MS method was developed for screening, quantification and confirmation of 28 stimulants in equine plasma. The method has facilitated the equine doping control analysis for a large number of stimulants at very low concentrations. Additionally, the stabilities of 28 stimulants in different storage conditions were assessed.