Screening of methylenedioxyamphetamine- and piperazine-derived designer drugs in urine by LC-MS/MS using neutral loss and precursor ion scan.

This study describes a method for the screening of methylenedioxyamphetamine- and piperazine-derived compounds in urine by liquid chromatography-tandem mass spectrometry. These substances, characterized by possessing common moieties, are screened using precursor ion and neutral loss scan mode and then quantified in multiple reaction monitoring acquisition mode. Based on the product-ion spectra of different known molecules, chosen as 'model', characteristic neutral losses and product ions were selected: piperazines were detected in precursor ion scan of m/z 44 and neutral loss of 43 and 86 while amphetamines in precursor ion scan of m/z 133, 135 and 163. The applicability of the screening approach was studied in blank urine spiked with selected analytes and processed by solid-phase extraction. Linearity, matrix effect, precision, accuracy, limits of detection and limits of quantification were evaluated both for the screening and the quantification methods. The ability of the screening method to provide semi-quantitative data was demonstrated. This method appears to be a useful tool for the identification of designer drugs derived from piperazines or methylenedioxyamphetamines and can be potentially applied to other drug classes.