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Buechler J, Schwab M, Mikus G, Fischer B, Hermle L, Marx C, Grön G, Spitzer M, Kovar KA.
“Enantioselective quantitation of the ecstasy compound R- and S-N-ethyl-3,4-methylenedioxyamphetamine and its major metabolites in human plasma and urine”.
J Chromatogr B Analyt Technol Biomed Life Sci. 2003 Aug 08;793(2):207-22.
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Abstract
An enantioselective HPLC method has been developed and validated for the stereospecific analysis of N-ethyl-3,4-methylenedioxyamphetamine MDE and its major metabolites N-ethyl-4-hydroxy-3-methoxyamphetamine HME and 3,4-methylenedioxyamphetamine MDA. These compounds have been analyzed both from human plasma and urine after administration of 70 mg pure MDE-hydrochloride enantiomers to four subjects. The samples were prepared by hydrolysis of the o-glucuronate and sulfate conjugates using beta-glucuronidase/arylsulfatase and solid-phase extraction with a cation-exchange phase. A chiral stationary protein phase chiral-CBH was used for the stereoselective determination of MDE, HME and MDA in a single HPLC run using sodium dihydrogenphosphate, ethylendiaminetetraacetic acid disodium salt and isopropanol as the mobile phase pH 6.44 and fluorimetric detection lambdaex 286 nm, lambdaem 322 nm. Moreover, a suitable internal standard N-ethyl-3,4-methylenedioxybenzylamine was synthesized and qualified for quantitation purposes. The method showed high recovery rates >95 and limits of quantitation for MDE and MDA of 5 ng/ml and for HME of 10 ng/ml. The RSDs for all working ranges of MDE, MDA and HME in plasma and urine, respectively, were less than 1.5. After validation of the analytical methods in plasma and urine samples pharmacokinetic parameters were calculated. The plasma concentrations of R-MDE exceeded those of the S-enantiomer ratio R:S of the area under the curve, 3.1 and the plasma half time of R-MDE was longer than that of S-MDE 7.9 vs. 4.0 h. In contrast, the stereochemical disposition of the MDE metabolites HME and MDA was reversed. Concentrations of the S-metabolites in plasma of volunteers were much higher than those of the R-enantiomers.
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