GLC identification and determination of 3,4-methylenedioxyamphetamine (MDA) from plasma and urine.

A GLC method for qualitative and quantitative determination of 3,4-methylenedioxyamphetamine in biological fluids is described. After extraction of the drug and the internal standard, 4-methoxyamphetamine, from plasma and urine, the solvent is evaporated and the residue is mixed with 20 mul of freshly distilled ether. Aliquots (1-2 mul) then are injected into the gas chromatograph. Both the drug and the internal standard give well-separated symmetrical peaks. Flame-ionization detection allows concentrations of 0.125 mug of 3,4-methylenedioxyamphetamine from plasma to be determined with a precision of 3.16%. The method is applicable to the estimation of 4-methoxyamphetamine, employing 3,4-methylenedioxyamphetamine as the internal standard. For identification purposes, various derivatives such as Schiff bases, isothiocyanates, trifluoroacetates, and heptafluorobutyrates of both compounds were formed following extraction from urine and their GLC behavior was investigated. Derivative formation was confirmed by GLC-mass spectrometry. Mass spectral data for these derivatives are presented.