Open this publication in new window or tab >>2004 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]
The studies presented in this thesis were part of a pan-European project, and they describe the research performed to develop a method for comparing amphetamine samples. The work included the following: optimisation of a method for profiling of amphetamine by gaschromatography (GC); optimisation of a technique for preparing samples for GC analysis; testing and evaluation of the abilities of a number of distance metrics to discern links between amphetamine samples originating from the same batch of synthesis analysed using the method developed in the current studies.
Street amphetamine contains hundreds of different by-products (target compounds), many of which have been identified and found to come from the different conditions used in the manufacturing process. Therefore, the main objective of developing the GC method was to optimise separation and quantification of the target compounds. The best separation was achieved using a DB-35MS capillary column. For quantification, mass spectrometry (MS) in the scan mode employing one target ion seemed to perform best, because this technique provided superior selectivity, and also made it possible to use mass spectra to identify target compounds. In addition, MS detection proved to offer excellent between-laboratory reproducibility.
The conditions used to prepare amphetamine samples for liquid-liquid extraction (LLE) andsolid-phase extraction (SPE) were also optimised. The sample preparation methods gave similar results but it was easier to use LLE, hence it was chosen for further sample preparation.
The ability of various numerical methods to find links between amphetamine samples was tested on GC-MS data of 26 target compounds that had been transformed by various pretreatment techniques. The best results were obtained when using Pearson correlation applied to data transformed by normalisation followed by applying fourth root.
It was also demonstrated that the amphetamine profiling method developed in the current studies was superior to a procedure already in use in a number of forensic laboratories in Europe.
Place, publisher, year, edition, pages
Linköping: Linköping University, 2004. p. 57
Series
Linköping Studies in Science and Technology. Dissertations, ISSN 0345-7524 ; 879
National Category
Organic Chemistry
Identifiers
urn:nbn:se:liu:diva-179057 (URN)9173739626 (ISBN)
Public defence
2004-05-27, Majoren, Brigaden, Linköpings garnisonsområde, Linköping, 10:15
Opponent
Note
All or some of the partial works included in the dissertation are not registered in DIVA and therefore not linked in this post.
2021-09-092021-09-092023-02-23Bibliographically approved