Analysis of amphetamine-type stimulants and their metabolites in plasma, urine and bile by liquid chromatography with a strong cation-exchange column-tandem mass spectrometry

The aim of this work was to develop and validate a method for analysing amphetamine-type stimulants (ATSs) and their metabolites in plasma, urine and bile by liquid chromatography with a strong cation-exchange column-tandem mass spectrometry, and to apply it to the pharmacokinetic study of ATSs. 3,4-Methylenedioxymethamphetamine, methamphetamine, ketamine and their main metabolites, 4-hydroxy-3-methoxymethamphetamine, 3,4-methylenedioxyamphetamine, p-hydroxymethamphetamine, amphetamine and norketamine, were simultaneously quantified by the new method (50-5000 ng/ml). The coefficients of variation and the percent deviations for the eight compounds were in the range of 0.2 to 5.3% and -9.4 to +12.8%, respectively. The recoveries were over 90% in all biological samples tested. This method was effective for the separation and the identification of ATSs and their main metabolites having amine moieties in plasma, urine and bile, and was applicable to pharmacokinetic analysis of methamphetamine, ketamine and their main metabolites in biological samples. This analytical method should be useful for the pharmacokinetic analysis of ATSs.