Forensic electrochemistry: Simultaneous voltammetric detection of MDMA and its fatal counterpart dr Death (PMA)

Abstract

The simultaneous detection of substances present in drugs of abuse is increasingly important since some materials are known for their high mortality rate. One drug that received considerable attention is para-methoxyamphetamine (PMA), commonly known as 'Dr Death'-this substance is linked with several deaths internationally and can often be found together with 3,4-methylenedioxymethamphetamine (MDMA) in drugs sold under the alias ecstasy, a very popular drug of abuse. This work reports for the first time the detection and quantification of MDMA and PMA simultaneously through an electrochemical technique using screen-printed graphite electrodes (SPEs). The electroanalytical sensing of MDMA/PMA, MDMA and PMA are explored directly at bare unmodified SPEs yielding a detection limit (3σ) corresponding to 0.25 μg mL-1/0.14 μg mL-1 for MDMA/PMA, 0.04 μg mL-1 MDMA and 0.03 μg mL-1 PMA. Raman spectroscopy and presumptive colour tests were also performed on MDMA/PMA, MDMA and PMA using the Marquis, Mandelin, Simon's and Robadope tests but were found to not be able discriminate when PMA and MDMA are both present in the same samples. We report a novel electrochemical protocol for the sensing of PMA and MDMA which is independently validated in a synthetic (MDMA/PMA) sample with HPLC.