Enantioselective determination of 3,4-methylene-dioxymethamphetamine and two of its metabolites in human urine by cyclodextrin-modified capillary zone electrophoresis.
Using capillary zone electrophoresis with a phosphate buffer at pH 2.5 containing 30 mM (2-hydroxypropyl)-beta-cyclodextrin as chiral selector, the simultaneous separation of the enantiomers of 3,4-methylenedioxymethamphetamine (MDMA or Ecstasy) and its two metabolites 4-hydroxy-3-methoxymethamphetamine (HMMA) and 3,4-methylenedioxyamphetamine (MDA) in human urine is reported. The assay described is based upon enzymatic hydrolysis of conjugated HMMA (major urinary metabolite) and solid-phase extraction followed by injection of a few nL of the extract onto a 50 microm internal diameter (ID) fused-silica capillary of 60 cm length. Solutes are detected via on-column absorbance at 195 nm. For 375 ng/mL drug levels, intraday and interday imprecision is < 4%. With 5 mL urine samples, the detection limit is in the 20-50 ng/mL range. Via analysis of the urines of two patients, the metabolism of MDMA is demonstrated to be enantioselective, with significantly higher urinary amounts of R-(-)-MDMA being excreted compared to S-(+)-MDMA. Within 72h after drug administration one patient was determined to excrete 42.28 and 10.16% of the racemic MDMA dose (1.5 mg/kg body weight) as R-(-) and S-(+)-MDMA enantiomers, respectively. Corresponding values for the second subject were found to be 28.63 and 9.34%. The metabolism of the enantiomers of the two metabolites showed interindividual differences. The first and second detected HMMA enantiomers represented 3.79 and 5.42% (first subject) and 8.51 and 4.36% (second), respectively, of the administered MDMA dose. For the MDA enantiomers, corresponding values were 2.44, 1.76, 0.75, and 0.79%, respectively.
Lanz
M
M
Department of Clinical Pharmacology, University of Bern, Switzerland.
Brenneisen
R
R
Thormann
W
W
D015104:3,4-Methylenedioxyamphetamine / Q000652:urine*; D003505:Cyclodextrins / Q000737:chemistry*; D004298:Dopamine / Q000031:analogs & derivatives / Q000652:urine; D019075:Electrophoresis, Capillary / Q000379:methods*; D006801:Humans; D008694:Methamphetamine / Q000031:analogs & derivatives* / Q000652:urine; D008968:Molecular Conformation; D018817:N-Methyl-3,4-methylenedioxyamphetamine / Q000652:urine*
D003505:Cyclodextrins; C079646:4-hydroxy-3-methoxymethamphetamine; C031105:3-O-methyl-alpha-methyldopamine; D008694:Methamphetamine; D015104:3,4-Methylenedioxyamphetamine; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D004298:Dopamine