Fast and Sensitive Chiral Analysis of Amphetamines and Cathinones in Equine Urine and Plasma Using Liquid Chromatography Tandem Mass Spectrometry

A simple, rapid, sensitive and reproducible method for enantiomer analysis of methamphetamine, amphetamine, cathinone and methcathinone was developed and validated. The compounds were extracted from equine plasma and urine using a fast liquid-liquid extraction procedure. Only one milliliter plasma and one hundred microliter urine sample is needed for analysis. The extraction procedure had good recovery (>70%) and the matrix effect was negligible. Enantiomer differentiation and confirmation were achieved using liquid chromatography with chiral stationary phase and mass spectrometry detection. The method demonstrated excellent reproducibility with intra-day and inter-day precision of lower than 5%. The lower limits of detection for all of the compounds studied here were at low pg/mL level for both plasma and urine. This is the first report of the analysis of four chiral compounds in equine plasma and urine. Routine application was demonstrated for (S)- and (R)-enantiomer differentiation.