Matrix Effect and Cross-Reactivity of Select Amphetamine-Type Substances, Designer Analogues, and Putrefactive Amines using the Bio-Quant Direct ELISA Presumptive Assays for Amphetamine and Methamphetamine
Luigino G. Apollonio, Ian R. Whittall, Dennis J. Pianca, Jennelle M. Kyd, William A. Maher
Journal of Analytical Toxicology May 1, 2007 DOI: 10.1093/jat/31.4.208 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Method evaluation study Peer reviewed |
|---|---|
| Topics | MDMA |
| Keywords | Pseudoephedrine Methamphetamine Chromatography Tyramine Pharmacology Phentermine Phenylpropanolamine Analyte |
| Citations | 51 |
| Key points | Bio-Quant Direct ELISA kits for amphetamine and methamphetamine are sensitive and specific enough for routine toxicological screening of blood, urine, and saliva, but show substantial cross-reactivity with several related compounds. |
Abstract
The aim of this study was to evaluate the Bio-Quant Direct ELISA assays for amphetamine and methamphetamine in the routine presumptive screening of biological fluids. Standard concentration curves of the target analytes were assayed to assess sensitivity, and known concentrations of common amphetamine-type substances (ephedrine, pseudoephedrine, phentermine), designer analogues (MDA, MDMA, MDEA, MBDB, PMA, 4-MTA, 2CB), and putrefactive amines (phenylethylamine, putrescine, tryptamine, tyramine) were analyzed to determine cross-reactivity. Results of the standard curve studies show the capacity of both Direct ELISA kits to confidently detect down to 3 ng/mL interday (PBS matrix; CVs 6.3-15.5%). Cross-reactivity relative to that of 50 ng/mL preparations of the target compounds demonstrated that the Direct ELISA kit for amphetamine also detected MDA (282%), PMA (265%), 4-MTA (280%), and phentermine (61%), and the Direct ELISA for methamphetamine also assayed positive for MDMA (73%), MDEA (18%), pseudoephedrine (19%), MBDB (8%), and ephedrine (9%). Matrix studies demonstrated that both ELISA kits could be applied to screening of blood, urine, and saliva to a concentration of 6 ng/mL or lower. In conclusion, the Bio-Quant Direct ELISA kits for amphetamine and methamphetamine are fast and accurate and have demonstrated themselves to be useful tools in routine toxicological testing.