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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

The Identification of Volatile Organic Compounds from Synthetic Cathinone Derivatives for the Development of Odor Mimic Training Aids

Francis, Vanquilla Shellman 01 June 2017 (has links)
Methylone, Ethylone, Methylenedioxypyrovalerone (MDPV), and α-Pyrrolidinopentiophenone (α-PVP) collectively referred to as bath salts are a new trend of illicit substances known as synthetic cathinones. Designed by chemically modifying the core structure of the compound cathinone, synthetic cathinones became prevalent within the United States around the mid-2000s. As a cheap and less controlled alternative to methylenedioxymethamphetamine (MDMA, ecstasy), it has become heavily abused, prompting emergency scheduling by federal regulators. Although regulations have been placed to halt incoming traffic of these drugs, lack of ground efforts still leave a large percentage of bath salts available. This study is two-fold, as it seeks to develop an extraction method for the development of Volatile Organic Compound profiles associated with various synthetic cathinones; and also determine the odorant used for canine recognition. The initial goal of this dissertation was to develop an extraction method to characterize various cathinone derivatives. The present study concluded that by employing a Polydimethylsiloxane Divinylbenzene (PDMS/DVB) coated fiber along with complimentary soft ionization techniques, the volatile components and all parent drugs could be identified within sixteen synthetic cathinone cases. The second goal of the dissertation was to assess and enhance the detection capabilities of narcotic detection teams. Canine field detection is routinely used to stop the increasing distribution influx of drugs into the United States that go undetected by standard procedures currently employed. Although currently canines can detect a multitude of drugs including heroin, cocaine, MDMA, and methamphetamine; this study revealed that more than ten canine teams (throughout south Florida) were not able to detect the presence of synthetic cathinones with current training material. While concerns have grown concerning the safety and reliability of canines being trained on various illicit substances, this research aimed to develop a safe, efficient, controlled alternative to training any canine for detection in the form of a Controlled Mimic Permeation System (COMPS). Field examination concluded that 3,4-methylenedioxypriophenone was the odorant responsible for the canine recognition of the cathinone derivative odor. Therefore a mimic training aid was developed and deployed within the field to enhance the detection capabilities of various canine teams.
12

Development of Advanced Capillary Electrophoresis Techniques with UV and Mass Spectrometry Detection for Forensic, Pharmaceutical and Environmental Applications

Fu, Hanzhuo 01 July 2014 (has links)
Capillary electrophoresis (CE) is a modern analytical technique, which is electrokinetic separation generated by high voltage and taken place inside the small capillaries. In this dissertation, several advanced capillary electrophoresis methods are presented using different approaches of CE and UV and mass spectrometry are utilized as the detection methods. Capillary electrochromatography (CEC), as one of the CE modes, is a recent developed technique which is a hybrid of capillary electrophoresis and high performance liquid chromatography (HPLC). Capillary electrochromatography exhibits advantages of both techniques. In Chapter 2, monolithic capillary column are fabricated using in situ photoinitiation polymerization method. The column was then applied for the separation of six antidepressant compounds. Meanwhile, a simple chiral separation method is developed and presented in Chapter 3. Beta cycodextrin was utilized to achieve the goal of chiral separation. Not only twelve cathinone analytes were separated, but also isomers of several analytes were enantiomerically separated. To better understand the molecular information on the analytes, the TOF-MS system was coupled with the CE. A sheath liquid and a partial filling technique (PFT) were employed to reduce the contamination of MS ionization source. Accurate molecular information was obtained. It is necessary to propose, develop, and optimize new techniques that are suitable for trace-level analysis of samples in forensic, pharmaceutical, and environmental applications. Capillary electrophoresis (CE) was selected for this task, as it requires lower amounts of samples, it simplifies sample preparation, and it has the flexibility to perform separations of neutral and charged molecules as well as enantiomers. Overall, the study demonstrates the versatility of capillary electrophoresis methods in forensic, pharmaceutical, and environmental applications.

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