Drug Testing and Analysis
April 22, 2019
Lewis Couchman, Anca Frinculescu, Catarina Sobreira et al.
35 citations
MDMA (Ecstasy) tablets collected in the UK between 2001 and 2018 show increasing MDMA content over time, with median free-base content exceeding 100 mg for the first time in 2018. Analysis of 412 tablets revealed dramatic within-batch content variability, with differences up to 136 mg. Dissolution testing on 247 tablets showed that tablets can be categorized as fast-, intermediate-, or slow-releasing, but no tablet characteristics predicted dissolution classification, meaning users cannot know a tablet's release profile beforehand. Within-batch variation in dissolution rate was also observed. Rapid assessment of MDMA content alone does not account for variability in remaining tablets in a batch or dissolution profiles. High-content, slow-releasing tablets may cause delayed or prolonged toxicity, increasing risk of re-dosing if absorption is delayed.
ChemRxiv
June 9, 2026
Matthew Gardner, Alexander Power, Anca Frinculescu et al.
A low-cost, field-portable device using Hybridized Spectral Fingerprinting (HSF) and deep learning can rapidly screen illicit drug samples for MDMA dosage and cocaine/ketamine purity. A convolutional neural network trained on 62 GC-EI-MS quantified MDMA tablets classified samples into 1–170 mg or 170–300 mg dosage brackets, achieving 98% accuracy on 195 external test samples. Another model trained on 1H NMR quantified cocaine and ketamine samples provided presumptive identification and semi-quantitative purity estimation with 96% accuracy on 47 external samples. The approach supports harm reduction and police screening by alerting on potentially harmful MDMA tablets and estimating cocaine and ketamine purity.
Journal of pharmaceutical and biomedical analysis
May 30, 2022
Anca Frinculescu, Alexander F G Maier, Trevor Shine et al.
A method for measuring MDMA content in ecstasy tablets using a compact 60 MHz benchtop NMR spectrometer was validated against UNODC guidelines. The method showed good specificity, selectivity, linearity, precision, and accuracy. Among seized tablets, the lowest MDMA free base detected was 9.35 mg in a piperazine mix, and the highest was 237.55 mg. The median MDMA amount in 2022 was 9.1% lower than pre-pandemic 2019 data but still higher than the 105 mg median reported in 2018. Within-batch variation was insignificant for one seizure but greater for another, indicating a single tablet's content may not represent the whole batch. The upward dosage trend underscores the need for ongoing monitoring and prevention interventions.