MDMA impurity profiling is used to determine the synthesis route of exhibits, and can be used to link separate exhibits to each other and to clandestine laboratories based on the impurities present. Profiles are typically generated using a liquid-liquid extraction (LLE) procedure and gas chromatography-mass spectrometry (GC MS). However, headspace solid phase microextraction (HS-SPME) is used in some forensic laboratories as an alternative extraction procedure, and has shown potential benefits. In addition, GC temperature programs vary between forensic laboratories, making comparisons of chromatographic data difficult.The aim of this research was to compare the LLE and HS-SPME procedures, as well as four GC temperature programs found in the literature, to determine their effects on the ability to associate replicates and discriminate exhibits of MDMA. Principal components analysis (PCA) was used to evaluate the data, and it was determined that HS-SPME provided increased discrimination of exhibits over LLE. While LLE provided higher precision of peak areas and, therefore, closer clustering of replicates, HS SPME allowed for the extraction of several trace impurities, which provided additional discriminatory power over LLE. In the temperature program investigation, one temperature program was more successful than the others at associating and discriminating samples. However, this temperature program was significantly longer than the rest, therefore further investigation is needed to determine the beneficial parameters of this program and create a shorter, more practical temperature program.
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