Evaluation of Immunoassays for the Determination of MDMA and Cannabinoids in Urine Samples
AHAI CHANG LUA1*, AN-REN HU1, BEE-FEN LIN1, PEI-CHI YEH1, HUEI-RU LIN1 AND YUNG-TE TSENG2,3
1. Department of Medical Technology, Tzu Chi University, 701 Section 3, Chung Yan Road, Hualien, Taiwan 970 R. O. C.
2. Department of Laboratory Medicine, Taipei City Psychiatric Hospital, 309 Sung-Te Rd. Taipei, Taiwan 10510 R. O. C.
3. Po-Ai Hospital, 83 Nan Chan St. Lo-Tong, I-Lan, Taiwan, 26514 R. O. C.
(Received: July 16, 2002; Accepted: November 4, 2002)
ABSTRACT
Methylenedioxymethamphetamine (MDMA) is structurally related to methamphetamine (MA). There are many different commercially available immunoassay (IA) reagents for the initial screening of amphetamine and/or methamphetamine. These reagents may be employed to detect MDA/MDMA in urine samples. In order to select a suitable reagent for the initial screening of MDMA in urine samples, we evaluated 7 different amphetamine immunoassay reagents: Emit d.a.u. Monoclonal Amphetamine/Methamphetamine; Emit II Plus Monoclonal Amphetamine/Methamphetamine; Emit d.a.u. Amphetamine Class; DRI Amphetamine; AxSYM Amphetamine/Methamphetamine II; Abuscreen Online Amphetamine and Cedia Amphetamine/Ecstasy. We also determined the cross reactivity of these reagents with MDA, MDMA, MBDB, MDEA and other phenethylamines. These IA reagents were employed to screen a group of 146 urine samples collected from pub patrons. Results of the initial screening were compared with results obtained with gas chromatography/mass spectrometry (GC/MS). Five of the IA assays were acceptable for the initial screening of MDMA, except the Emit II Plus Monoclonal Amphetamine/Methamphetamine reagent and Emit d.a.u. Class Amphetamine reagent. Results obtained with Emit II reagent showed high false negatives, while results obtained with Emit d.a.u. Class reagent showed high false positives.
We evaluated 5 different IA for cannabinoids. Results of the initial screening of 74 urine samples collected from pub patrons were compared with results obtained by GC/MS. There are 12 confirmed positives with GC/MS. Results obtained with DRI reagent showed no false negatives, while results obtained with Emit, Abuscreen Online, AxSYM and Cedia reagents have 4, 2, 3 and 4 false negatives, respectively.
Key words: MDMA, cannabinoids, immunoassay, urine samples, pub