title: Application of the Syva EMIT and Abbott TDx amphetamine immunoassays to the detection of 3,4-methylene-dioxymethamphetamine (MDMA) and 3,4-methylene-dioxyethamphetamine (MDEA) in urine.
abstract: MDMA and MDEA are hallucinogenic analogs of amphetamine. The need for laboratory monitoring of these substances has developed as a result of their increased recreational use. Since the Abbott TDx and Syva EMIT-d.a.u. immunoassays are commonly used tests for urine monitoring of drugs-of-abuse, the amphetamine assay of each manufacturer was assessed to determine the degree of cross-reactivity with MDMA and MDEA. Cross-reactivity was evaluated using a series of MDMA- and MDEA-spiked urine samples. Testing was performed over a two-day period with 3 runs/day and each sample run in duplicate. The Syva EMIT d.a.u. amphetamine assay was positive only at the highest concentration standard (10.0 micrograms/mL) for both MDMA and MDEA. Consequently, no further testing was performed with this assay. Calibration curves were generated for the TDx runs and percent cross-reactivity determinations were made. Precision for the TDx data was evaluated based on within-day and between-day coefficients of variation (CV). CVs for MDMA runs were below 6% for within-day and below 5% for between-day runs. Values of CV for MDEA were below 16% for both within-day and between runs; CVs were less than 2.5% for positive values. Cross-reactivity for MDMA ranged from 18% (10.00 micrograms/mL) to 118% (0.15 microgram/mL). Cross-reactivity for the MDEA standards ranged from 12% (10.00 micrograms/mL) to 47% (0.15 micrograms/mL). The presence of MDMA and/or MDEA in samples resulting in a negative EMIT-d.a.u. test and a positive TDx test was confirmed by GC/MS analysis.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Pharmacology, Louisiana State University Medical Center, Shreveport 71130.
authors.forename: G W
authors.initials: GW
authors.lastname: Kunsman
authors.forename: J E
authors.initials: JE
authors.lastname: Manno
authors.forename: K R
authors.initials: KR
authors.lastname: Cockerham
authors.forename: B R
authors.initials: BR
authors.lastname: Manno
mesh_terms: D015104:3,4-Methylenedioxyamphetamine / Q000031:analogs & derivatives / Q000652:urine*; D000662:Amphetamines / Q000652:urine*; D002623:Chemistry Techniques, Analytical; D003429:Cross Reactions; D004305:Dose-Response Relationship, Drug; D005188:False Negative Reactions; D005454:Fluorescence Polarization / Q000379:methods; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D007124:Immunoenzyme Techniques; D018817:N-Methyl-3,4-methylenedioxyamphetamine; D015203:Reproducibility of Results
chemical_list: D000662:Amphetamines; D015104:3,4-Methylenedioxyamphetamine; D018817:N-Methyl-3,4-methylenedioxyamphetamine; C051800:3,4-methylenedioxyethamphetamine