Characterisation and profiling of ecstasy tablets
In addition to identifying the presence of a specific controlled drug in an exhibit and measuring its concentration, forensic drug laboratories are requested in certain cases or as a routine to provide additional information that may be helpful to the investigation process. On the basis of their chemical and physical characteristics, seized drugs may be profiled and linked to common sources or routes of distribution. Chapter 1 is an introduction to the illicit drug production from cultivation to manufacturing and trafficking. Chapter 2 describes the role of the drug chemist and includes characterisation of seizures, that is identification, quantification, and comparison of illicit drugs. Chapter 3 provides a literature review of the different analytical methods used in the area of drug profiling. This project has been on the subject of drug profiling with focus on the ringsubstituted amphetamine, 3,4 methylenedioxymethamphetamine (MDMA) or ecstasy as it is widely called. Among the main objectives of this study was the development and optimisation of a new extraction procedure, solid phase extraction, for impurities in seized ecstasy tablets. The instrumental analysis of impurities found in ecstasy tablets usually require a preliminary process to extract, isolate, and concentrate these impurities from the total tablet content. In the process, interfering materials are removed, and the required substances are concentrated into a solvent that is suitable for introduction into the instrument. Chapter 4 describes the development of a solid phase extraction (SPE) procedure and also an evaluation of a comparison procedure of liquid-liquid extraction (LLE) and SPE for extracting impurities in ecstasy tablets for profiling purposes. Solid phase extraction of impurities in ecstasy tablets proved to be more efficient than the traditional liquidliquid extraction. SPE provided impurity peaks with higher intensities than did LLE and a shorter extraction time. Another area of research was the use of infrared technology as an additional tool for profiling ecstasy tablets as seen in Chapter 5. Infrared method can serve as an elimination or screening step for gross clustering or grouping of exhibits. In chapter 6 the synthesis of MDMA using different synthetic routes to acquire authentic samples of impurities which are usually present in street samples were performed. These authentic samples were analysed and their mass spectra and retention indices were used to identify impurities in actual street samples to determine their route of synthesis. In chapter 7 ecstasy tablets confiscated within the UK were analysed to establish their route(s) of synthesis using the data of the authentic compounds synthesised earlier. The main contributions of this project were: 1. Developing a solid phase extraction procedure as an alternative to the conventional liquid-liquid extraction procedure. SPE provided extraction with no cross contamination of phases and no emulsion problem, as with LLE, due to the presence of fatty acids in ecstasy tablets. 2. Developing a simple and fast infrared method as a screening or elimination tool for ecstasy profiling. 3. Study of the synthetic routes of ecstasy samples within the UK with the aid of route-specific authentic impurity compounds synthesised in-house.