Instability of the ecstasy market and a new kid on the block: mephedrone

Recently, several reports have indicated instability of the ecstasy market in the Netherlands and other EU countries. In the current study, we demonstrate this instability in the Netherlands, showing a decrease of ecstasy tablets containing 3,4-methylenedioxymetamphetamine (MDMA) by more than 50% in 2009. In addition, we describe a partial replacement of MDMA in tablets sold as ecstasy by a previously unseen substance, mephedrone (or 4-methylmethcathinone). Mephedrone was quantified and ecstasy tablets contained between 96 and 155 mg of this new compound. So far, no studies about mephedrone's effects have been published. For this study, we gathered information on the acute subjective effects of mephedrone from 70 regular ecstasy users. Overall, the majority of users considered the effects enjoyable. Mephedrone seemed to evoke effects similar to other amphetamine type psychostimulants, including MDMA. In contrast to MDMA, however, mephedrone induced strong feelings of craving in most users. If the unstable ecstasy market situation persists, the potential of mephedrone to substitute for MDMA might be substantial. Mephedrone, sold as ecstasy, is therefore likely to be a valid cause for health concer

Development of a harmonised method for the profiling of amphetamines: IV. Optimisation of sample preparation

The suitability of liquid–liquid extraction (LLE) and solid-phase extraction (SPE) for the preparation of impurity extracts intended for gas chromatographic profiling analyses of amphetamine were evaluated. Both techniques were optimised with respect to the extraction of selected target compounds by use of full factorial designs in which the variables affecting the performance were evaluated. Test samples consisted of amphetamine synthesised by the Leuckart reaction, by reductive amination of benzyl methyl ketone and by the nitrostyrene route. The performance of LLE and SPE were comparable in terms of repeatability and recovery of the target compounds. LLE was considered the better choice for the present harmonised amphetamine profiling method due to the lack of information on the long-term stability of SPE columns

Development of a harmonised method for the profiling of amphetamines: III. Development of the gas chromatographic method

This study focused on gas chromatographic analysis of target compounds found in illicit amphetamine synthesised by the Leuckart reaction, reductive amination of benzyl methyl ketone, and the nitrostyrene route. The analytical method was investigated and optimised with respect to introduction of amphetamine samples into the gas chromatograph and separation and detection of the target substances. Sample introduction using split and splitless injection was tested at different injector temperatures, and their ability to transfer the target compounds to the GC column was evaluated using cold on column injection as a reference. Taking the results from both techniques into consideration a temperature of 250 °C was considered to be the best compromise. The most efficient separation was achieved with a DB-35MS capillary column (35% diphenyl 65% dimethyl silicone; 30 m × 0.25 mm, df 0.25 μm) and an oven temperature program that started at 90 °C (1 min) and was increased by 8 °C/min to 300 °C (10 min). Reproducibility, repeatability, linearity, and limits of determination for the flame ionisation detector (FID), nitrogen phosphorous detector (NPD), and mass spectrometry (MS) in scan mode and selected ion monitoring (SIM) mode were evaluated. In addition, selectivity was studied applying FID and MS in both scan and SIM mode. It was found that reproducibility, repeatability, and limits of determination were similar for FID, NPD, and MS in scan mode. Moreover, the linearity was better when applying FID or NPD whereas the selectivity was better when utilising the MS. Finally, the introduction of target compounds to the GC column when applying injection volumes of 0.2 μl, 1 μl, 2 μl, and 4 μl with splitless injection respectively 1 μl with split injection (split ratio, 1:40) were compared. It was demonstrated that splitless injections of 1 μl, 2 μl, and 4 μl could be employed in the developed method, while split injection and splitless injections of 0.2 μl should be avoided

Development of a harmonised method for the profiling of amphetamines: II. Stability of impurities in organic solvents

The present study focused on the stability of 22 amphetamine impurities dissolved in six organic solvents: isooctane, toluene, ethanol, dichloromethane, ethyl acetate, and diethyl ether. The aim was to find the most inert, and thereby most suitable, solvent for amphetamine profiling. Mixtures of the impurities were prepared in the different solvents, and changes in the concentrations of the individual compounds over-time were monitored by gas chromatographic analysis after 0, 4, 12, 24, 48, and 96 h. Isooctane and toluene provided the most inert conditions, although, a few of the impurities were insufficiently stable in these two solvents. The present experiments were performed as a part of the development of a harmonised method for profiling of amphetamine. The results can be used to support the choice of organic solvents for sample preparation. They also provide information about the stability of the impurities that are found in profiles of illicit amphetamine. This is essential due to the fact, that unstable compounds can have a negative influence on the comparison of profiles

Development of a harmonised method for the profiling of amphetamines: I. Synthesis of standards and compilation of analytical data

Reference material was synthesised for 21 substances that are frequently present as synthetic impurities, i.e. by-products, in illicitly produced amphetamine. Each of these substances is a typical by-product for at least one of the three approaches most often used to synthesise amphetamine, namely, the Leuckart, the reductive amination of benzyl methyl ketone, and the nitrostyrene routes. A large body of data on the substances was recorded, including the following: mass spectra, ultraviolet spectra, Fourier transform infrared spectra, infrared spectra in gas phase, and 1H NMR and 13C NMR spectra