The DRI Ecstasy Enzyme Immunoassay is a homogeneous enzyme immunoassay intended for the qualitative or semi-quantitative determination of ecstasy drugs in human urine. The assay provides a simple and rapid analytical screening procedure for detecting ecstasy drugs at a cutoff level of 500 ng/mL.
The DRI® Ecstasy assay utilizes liquid, ready-to-use reagents and calibrators. The assay uses specific antibodies, which can detect ecstasy drugs in urine with minimal cross-reactivity to various amphetamine compounds. The assay is based on competition between a drug labeled with glucose-6-phosphate dehydrogenase (G6PDH) enzyme, and free drug from the urine sample for a fixed amount of specific antibody binding sites. In the absence of free drug from the sample,the specific antibody binds the drug labeled with G6PDH causing a decrease in enzyme activity.This phenomenon creates a direct relationship between drug concentration in urine and enzyme activity. The enzyme G6PDH activity is determined spectrophotometrically at 340 nm by measuring its ability to convert nicotinamide adenine dinucleotide (NAD) to NADH.