Validated liquid chromatographic–electrospray ionization mass spectrometric assay for simultaneous determination of 3,4-methylenedioxymethamphetamine and its metabolites 3,4-methylenedioxyamphetamine, 3,4-dihydroxymethamphetamine, and 4-hydroxy-3-methoxym

3,4-Methylenedioxymethamphetamine (MDMA) is a recreational drug with neurotoxic potential. Pharmacokinetic data of MDMA and its metabolites may shed light on the mechanism of MDMA neurotoxicity. An LC–MS assay with electrospray ionization (ESI) is presented for quantifying MDMA and its metabolites 3,4-methylenedioxyamphetamine (MDA), 3,4-dihydroxymethamphetamine (HHMA), and 4-hydroxy-3-methoxymethamphetamine (HMMA) in squirrel monkey plasma. The method involved enzymatic conjugate cleavage and protein precipitation. Separation was achieved within 14 min. The method was validated according to international guidelines with respect to selectivity, linearity, accuracy, precision, recovery, and matrix effect. The present method should prove useful for acquiring pharmacokinetic and toxicokinetic data in squirrel monkeys.