Dissertations / Theses: 'Forensic Drugs'

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Swortwood, Madeleine Jean. "Comprehensive Forensic Toxicological Analysis of Designer Drugs." FIU Digital Commons, 2013. http://digitalcommons.fiu.edu/etd/997.

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New designer drugs are constantly emerging onto the illicit drug market and it is often difficult to validate and maintain comprehensive analytical methods for accurate detection of these compounds. Generally, toxicology laboratories utilize a screening method, such as immunoassay, for the presumptive identification of drugs of abuse. When a positive result occurs, confirmatory methods, such as gas chromatography (GC) or liquid chromatography (LC) coupled with mass spectrometry (MS), are required for more sensitive and specific analyses. In recent years, the need to study the activities of these compounds in screening assays as well as to develop confirmatory techniques to detect them in biological specimens has been recognized. Severe intoxications and fatalities have been encountered with emerging designer drugs, presenting analytical challenges for detection and identification of such novel compounds. The first major task of this research was to evaluate the performance of commercially available immunoassays to determine if designer drugs were cross-reactive. The second major task was to develop and validate a confirmatory method, using LC-MS, to identify and quantify these designer drugs in biological specimens. Cross-reactivity towards the cathinone derivatives was found to be minimal. Several other phenethylamines demonstrated cross-reactivity at low concentrations, but results were consistent with those published by the assay manufacturer or as reported in the literature. Current immunoassay-based screening methods may not be ideal for presumptively identifying most designer drugs, including the “bath salts.” For this reason, an LC-MS based confirmatory method was developed for 32 compounds, including eight cathinone derivatives, with limits of quantification in the range of 1-10 ng/mL. The method was fully validated for selectivity, matrix effects, stability, recovery, precision, and accuracy. In order to compare the screening and confirmatory techniques, several human specimens were analyzed to demonstrate the importance of using a specific analytical method, such as LC-MS, to detect designer drugs in serum as immunoassays lack cross-reactivity with the novel compounds. Overall, minimal cross-reactivity was observed, highlighting the conclusion that these presumptive screens cannot detect many of the designer drugs and that a confirmatory technique, such as the LC-MS, is required for the comprehensive forensic toxicological analysis of designer drugs.

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2

Andrews, Anthony Robert John. "The chemiluminescence detemination of drugs of forensic interest." Thesis, University of Hull, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.306129.

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3

Lutfi, Layal Anton. "Stability of drugs of forensic interest in post mortem blood." Thesis, University of Glasgow, 1998. http://theses.gla.ac.uk/7085/.

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The stability study of drugs of forensic interest in human post-mortem blood is an important forensic study, because in some cases, a requirement for the laboratory to undertake a full drug screening is after a few months of storage due to a need for new evidence. Therefore, it is necessary and important to know if drugs are stable over a period of time under different conditions to enable a solid interpretation to be made from any results. Some studies have been published on the stability of drugs at different temperatures but none had covered the whole set of drugs that has been studied in this thesis. The periods of study that have been covered by other studies varied from a few days to a maximum of 70 weeks, but again not all drugs have been covered. The drugs studies in this thesis are two sets of drugs, benzodiazepines and tricyclic antidepressants, their stability being determined over twelve months and at three different temperatures 25,5 and -20°C. In this thesis, blood was 'spiked' with eight drugs, Diazepam, Temazepam, Triazolam, Desmethyldiazepam, Amitriptyline, Nortriptyline, Imipramine and Chlorpromazine. The samples were stored with blanks at different temperatures for different storage times. Each month a number of samples were removed from storage and analysed to test the effect of storage time and temperature on drug concentration. Different solid phase and liquid-liquid extraction methods were tested for the determination of benzodiazepines. Liquid-liquid extraction methods for - 2 - the determination of Diazepam, Temazepam, desmethyldiazepam and Triazolam proved after study to be tedious and time-consuming. A method based on solid phase extraction was used to determine the four benzodiazepine drugs. The extraction method gave good recoveries and was highly efficient. The method of analysis used for the determination of stability of benzodiazepine drugs was the high performance liquid chromatography (HPLC) method. Tricyclic antidepressant drugs are the other drugs studied for their stability in blood. Different solid phase extraction methods were used for the determination of drugs in post-mortem blood but gave poor recoveries. The best method of extraction used was a liquid-liquid extraction method which yielded high recoveries and proved to be quick. The method of analysis used for the determination of tricyclic antidepressants for the purpose of stability of the study was gas chromatography (GC). At a recognised toxic level for each drug under study a reasonable amount of the drug was found to be detectable after one year at storage regardless of the storage temperature or media. The decrease rate of each drug concentration with time at the three storage conditions (25, 5 and -200e) was obtained.

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4

Alshamaileh, M. Y. "Novel strategies for the analysis of drugs of abuse." Thesis, University of Lincoln, 2016. http://eprints.lincoln.ac.uk/23695/.

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The data presented in this thesis has been organized in three parts: First part included the development and validation of a quantitative HPLC-DAD analytical method of mephedrone after extraction from spiked whole blood and serum samples, alone and with methcathinone. The second part included in vitro metabolism of mephedrone and other NPS, which are methoxetamine and methcathinone, using an in-house prepared in vitro metabolic system, namely liver microsomes, followed by performing analysis for the drugs and their proposed metabolites utilizing LC-MS. Third part included in vitro studies of selected NPS using purchased HepaRG and hepatocytes. In vitro study included in vitro cytotoxicity studies of 4-fluoromethamphetamine, mephedrone, methoxetamine and methcathinone, and analytical studies of these drugs of abuse and their potentially produced metabolites using GC-MS. In the first part of this thesis, a HPLC method for the analysis of mephedrone after LLE from blood matrix was developed and validated and shown to be linear with R2> 0.995, precise with intraday and interday RSD values of 4.36 and 4.77% respectively and LOD and LOQ of 0.025 and 0.082 μg/mL respectively. Recovery percentages were low and ranged between 28-37%. Emulsion formation was the major problem effaced which negatively affected recovery and precision values. The previously developed method was optimised and fully validated for the simultaneous analysis of mephedrone and methcathinone after liquid-liquid extraction (LLE) from whole blood and serum samples. The LLE method was optimised through selection of extraction solvent and adjustment of pH values achieving the best validation parameters and minimal emulsion formation. The LLE protocol involved extraction with a mixture of dichloromethane: n-butanol (80:20 v: v) after buffering the sample with borate buffer pH=9.2 and using aniline as internal standard. The HPLC-DAD method was optimized, using reverse mode chromatography and buffered mobile phase of (acetate buffer pH 4.1: ACN – 85:15) for qualitative and quantitative analysis of these drugs in less than 10 minutes under isocratic elution and ambient temperature. The method was fully validated for both drugs and showed to be linear over the specified range of 0.1-10 μg/mL with R2 > 0.99 for both drugs. The accuracy was assessed by calculating percentage recovery at different concentrations for xii both drugs, and retained recovery percent between 84-110%. For repeatability and intermediate precision tests, RSD values were ≤ 6.73%. Specificity was assessed by good resolution between the peaks and by checking peak purities. Limit of detection and limit of quantification, calculated mathematically for both drugs either extracted from whole blood or serum samples, were 0.010- 0.013 μg/ml and 0.032 - 0.043 μg/mL, respectively. In the second part, in vitro studies on the metabolism of the selected NPS using pig liver microsomes and liquid chromatography-mass spectrometry (LC-MS) analysis were performed. Microsomes were prepared by a conventional ultracentrifugation method. In brief, pig liver was brought freshly from local abattoir, sliced into small pieces, homogenised and ultra-centrifuged to produce microsomes and S9 fractions. Produced microsomes were incubated with the drugs of interest under optimised conditions and followed by analysis utilizing LC-MS for the detection of the drugs and the potentially produced metabolites. It was possible to detect two metabolites of the drug mephedrone, hydroxytolyl-mephedrone and nor-dihydro mephedrone. For MXE, one metabolite produced by the O-demethylation was detected and it identity confirmed by MS/MS study to be o-desmethyl-MXE. Another metabolite was detected is suggestively produced by the reduction of the ketone moiety to produce dihydro-MXE or by two steps of O-demethylation and hydroxylation to produce O-desmethyl –hydroxy-MXE. However, due to low intensity signal recorded, MS/MS study was not conclusive for the identity of the molecule In the third part, two types of hepatocytes were used for the study of the metabolism and cytotoxicity of the selected NPS - Mephedrone, Methoxetamine, Methcathinone and 4-Fluoromethamphetamine. Studying the metabolism of selected NPS followed utilizing HepaRG™ followed by GC-MS analysis, it was possible to detect new peaks in the chromatograms of mephedrone and methcathinone which is suggestively the product of N-demethylation. However, it was not possible to detect any new peaks in the chromatograms of methoxetamine nor 4-flouromethamphetamine. The cytotoxicity study utilizing HepaRG cell line showed that these drugs have cytotoxic effects causing in vitro cell death, within the specified range of 4.0x10-2-1.6x101 mM. These drugs were able to cause 43-83% ii cell death, and EC50 values were 0.2323-0.6297 mM. The most potent drug was 4-fluoromethamphetamine, while mephedrone showed the least biological effect to produce.

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5

Björn, Niklas. "Database processing for identification of concomitant drug frequencies in a forensic material positive for antidepressant drugs." Thesis, Linköpings universitet, Institutionen för medicin och hälsa, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-107575.

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This article presents a study conducted on data containing drug concentrations. The data was obtained from femoral venous blood samples collected at medico legal autopsies in Sweden. Cases positive for antidepressant drugs were scrutinized and divided in to two groups for 15 antidepressant drugs: B‑cases, where the cause of death was intoxication with more than one drug detected in the blood sample. C‑cases, where the cause of death was NOT intoxication and at least one drug (the antidepressant) was detected in the blood sample. This data was then processed to find frequencies of concomitant drugs taken together with the antidepressant drugs. Frequencies of the most common concomitant drugs were then compared between B-cases and C-cases for each antidepressant drug. This revealed that the drugs dextropropoxyphene, ethanol, codeine, flunitrazepam, paracetamol, propiomazine and alimemazine were signifcantly more common as concomitant drugs in B-cases (intoxications) than in C‑cases (non‑intoxications). With regards to unknown interactions the most interesting combinations were: Propiomazine with mirtazapine, venlafaxine, citalopram or fluoxetine; Paracetamol with paroxetine; Flunitrazepam with mirtazapine, venlafaxine or citalopram; Codeine with mirtazapine or sertraline. These combinations should be further investigated.

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6

Ali, Esam M. A. "Applications of Raman Spectroscopic Techniques in Forensic and Security Contexts. The detection of drugs of abuse and explosives in scenarios of forensic and security relevance using benchtop and portable Raman spectroscopic instrumentation." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5267.

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Drug trafficking and smuggling is an ongoing challenge for law enforcement agencies. Cocaine smuggling is a high-value pursuit for smugglers and has been attempted using a variety of concealment methods including the use of bottled liquids, canned milk, wax and suspensions in cans of beer. In particular, traffickers have used clothing impregnated with cocaine for smuggling. Handling, transportation or re-packaging of drugs of abuse and explosives will inevitably leave residual material on the clothing and other possessions of the involved persons. The nails and skin of the person may also be contaminated through the handling of these substances. This research study describes the development of Raman spectroscopic techniques for the detection of drugs of abuse and explosives on biomaterials of forensic relevance including undyed natural and synthetic fibres and dyed textile specimens, nail and skin. Confocal Raman microscopy has been developed and evaluated for the detection and identification of particulates of several drugs of abuse and explosives on different substrates. The results show that excellent spectroscopic discrimination can be achieved between single particles and substrate materials, giving a ubiquitous non-destructive approach to the analysis of pico-gram quantities of the drugs and explosives in-situ. Isolating the particle in this way corresponds with an analytical sensitivity comparable with the most sensitive analytical techniques currently available e.g. the highly sensitive, yet destructive ionization desorption mass spectrometry. With the confocal Raman approach, this work demonstrates that definitive molecular-specific information can be achieved within seconds without significant interference from the substrate. The potential for the application of this technique as a rapid preliminary, forensic screening procedure is obvious and attractive to non-specialist operators as it does not involve prior chemical pretreatment ii or detachment of the analyte from the substrate. As a result, evidential materials can be analysed without compromising their integrity for future investigation. Also, the applications of benchtop and portable Raman spectroscopy for the in-situ detection of drugs of abuse in clothing impregnated with the drugs have been demonstrated. Raman spectra were obtained from a set of undyed natural and synthetic fibres and dyed textiles impregnated with these drugs. The spectra were collected using three Raman spectrometers; one benchtop dispersive spectrometer coupled to a fibre-optic probe and two portable spectrometers. High quality spectra of the drugs could be acquired in-situ within seconds and without any sample preparation or alteration of the evidential material. A field-portable Raman spectrometer is a reliable instrument that can be used by emergency response teams to rapidly identify unknown samples. This method lends itself well to further development for the in-situ examination by law enforcement officers of items associated with users, handlers and suppliers of drugs of abuse in the forensics arena. In the last section of this study, a portable prototype Raman spectrometer ( DeltaNu Advantage 1064) equipped with 1064 nm laser excitation has been evaluated for the analysis of drugs of abuse and explosives. The feasibility of the instrument for the analysis of the samples both as neat materials and whilst contained in plastic and glass containers has been investigated. The advantages, disadvantages and the analytical potential in the forensics arena of this instrument have been discussed.
Egyptian Government and Sohag University

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7

Ali, Esam Mohamed Abdalla. "Applications of Raman spectroscopic techniques in forensic and security contexts : the detection of drugs of abuse and explosives in scenarios of forensic and security relevance using benchtop and portable Raman spectroscopic instrumentation." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/5267.

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Drug trafficking and smuggling is an ongoing challenge for law enforcement agencies. Cocaine smuggling is a high-value pursuit for smugglers and has been attempted using a variety of concealment methods including the use of bottled liquids, canned milk, wax and suspensions in cans of beer. In particular, traffickers have used clothing impregnated with cocaine for smuggling. Handling, transportation or re-packaging of drugs of abuse and explosives will inevitably leave residual material on the clothing and other possessions of the involved persons. The nails and skin of the person may also be contaminated through the handling of these substances. This research study describes the development of Raman spectroscopic techniques for the detection of drugs of abuse and explosives on biomaterials of forensic relevance including undyed natural and synthetic fibres and dyed textile specimens, nail and skin. Confocal Raman microscopy has been developed and evaluated for the detection and identification of particulates of several drugs of abuse and explosives on different substrates. The results show that excellent spectroscopic discrimination can be achieved between single particles and substrate materials, giving a ubiquitous non-destructive approach to the analysis of pico-gram quantities of the drugs and explosives in-situ. Isolating the particle in this way corresponds with an analytical sensitivity comparable with the most sensitive analytical techniques currently available e.g. the highly sensitive, yet destructive ionization desorption mass spectrometry. With the confocal Raman approach, this work demonstrates that definitive molecular-specific information can be achieved within seconds without significant interference from the substrate. The potential for the application of this technique as a rapid preliminary, forensic screening procedure is obvious and attractive to non-specialist operators as it does not involve prior chemical pretreatment ii or detachment of the analyte from the substrate. As a result, evidential materials can be analysed without compromising their integrity for future investigation. Also, the applications of benchtop and portable Raman spectroscopy for the in-situ detection of drugs of abuse in clothing impregnated with the drugs have been demonstrated. Raman spectra were obtained from a set of undyed natural and synthetic fibres and dyed textiles impregnated with these drugs. The spectra were collected using three Raman spectrometers; one benchtop dispersive spectrometer coupled to a fibre-optic probe and two portable spectrometers. High quality spectra of the drugs could be acquired in-situ within seconds and without any sample preparation or alteration of the evidential material. A field-portable Raman spectrometer is a reliable instrument that can be used by emergency response teams to rapidly identify unknown samples. This method lends itself well to further development for the in-situ examination by law enforcement officers of items associated with users, handlers and suppliers of drugs of abuse in the forensics arena. In the last section of this study, a portable prototype Raman spectrometer ( DeltaNu Advantage 1064) equipped with 1064 nm laser excitation has been evaluated for the analysis of drugs of abuse and explosives. The feasibility of the instrument for the analysis of the samples both as neat materials and whilst contained in plastic and glass containers has been investigated. The advantages, disadvantages and the analytical potential in the forensics arena of this instrument have been discussed.

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8

Morrison, Calum M. "Chiral and achiral analysis of benzodiazepine and anti-anginal drugs in forensic toxicology." Thesis, University of Glasgow, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321443.

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9

Westraat, Hendrik. "Pilot study : Investigating the chemical composition of illegal drugs and the associated prevalence of the different drug types in the Bellville and Athlone police districts in the Western Cape, South Africa." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20916.

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Very little chemical information is known about substances being abused in South-Africa. This can be attributed to the fact that possession of drugs constitutes a criminal offence. Not much research is done, and with the exception of self-reported, rehabilitation institution data, from the South African Community Epidemiology Network on Drug Use (SACENDU) and the South African Police drug related arrest data, no other data on drugs and drug use, is publically available. Drugs are being manufactured from legal and illegal chemicals in clandestine laboratories, not complying with any health, safety or quality standards causing a serious health risk in communities. The strategy for the fight against drug abuse in South Africa, the National Drug Master Plan 2013-2017 (NDMP), is compiled by the Central Drug Authority (CDA). Without proper research, data to base decisions and strategies on and proper measuring of achievements, the implementation of the plan suffers as a consequence. The Forensic Science Laboratory (FSL) of the South African Police Service (SAPS), is responsible for the chemical testing of substances, suspected of being illegal drugs, for identification purposes. This supports the prosecuting of suspects during criminal procedures. With the active ingredient known, the use of street names e.g. Tik, Choef or Speed (all referring to methamphetamine) can be abandoned and confusion and misconceptions eliminated. This pilot study investigates the arrest data, in combination with the charge laid against the arrestee and the chemically identified active ingredient in each case. Arrest data revealed a 400% increase in drug related arrests over the last 10 years, while the NDMP requires a 10% decrease. It further highlights the fact that the measurement of success (number of arrests) in the SAPS, resulted in a focus on arresting persons in possession of drugs. The dealers and manufacturers were not adequately addressed and prevention, through chemical monitoring, suffered as a result. This study also clearly revealed that international trends are not a definite indication of the extent and type of drug abuse in South African Communities. The study further attempts to contribute, and to better describe the situation of drugs and drug abuse in communities. This in turn, will provide data to develop evidence based strategies, designed to meet the defined needs of communities, one of the aspects highlighted by the minister in the NDMP, namely an intervention based on reality and local statistics. It is therefore clear that a scientific understanding of the composition of abused substances can direct treatment, policy, prevention measures and provide intelligence to combat drug abuse and illegal drug manufacturing in South Africa.

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Al, Najjar Ahmed Omer. "Enhancement of Sensitivity in Capillary Electrophoresis: Forensic and Pharmaceutical Applications." Ohio University / OhioLINK, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1107276943.

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11

Allen, Desiree Lisa. "The applications of supercritical fluid and solid-phase extraction techniques for the recovery of drugs of abuse from biological matrices." Thesis, University of Glasgow, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.249963.

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12

Auckloo, Marie Belle Kathrina Mendoza. "A post-mortem toxicological investigation: Understanding the role of drugs of abuse in violent fatalities in Cape Town, South Africa." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20515.

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Violence and resulting injuries are critical health burdens worldwide, accounting for the death of millions of individuals annually. The literature reports an association between drug use and violence, providing data indicating that the use of psychoactive substances increases the risk of morbidity and mortality due to violent acts. South Africa has a long history of violence, with one of the highest rates of recorded violence- and injury-related deaths in the world. This is complicated by an increase in illicit substance use and abuse, particularly in the Cape Town Metropole, located within the Western Cape Province. The use of toxicological findings from victims of violent death (homicides, suicides, and accidents) to examine community-specific drug-related violence is slowly increasing in different parts of the world. In South Africa, however, monitoring drug trends in violent fatalities using toxicological analysis is uncommon, and hence drug toxicology of violent-related fatalities is limited. Divided into three contextual sections, this research study focuses on the post-mortem toxicology of violent deaths in a South African setting. The first section provides a general idea of the research problem and an initial development of the investigation process. The second section provides a theoretical basis for performing routine toxicological analyses in deaths due to violence, reports important research work conducted in the field worldwide, and emphasizes the need to monitor toxicological data derived from violent fatalities in Cape Town, South Africa. The last section, in the form of a manuscript, presents the overall research study including the methodology, outcomes, and concluding findings in a concise and illustrative manner. The primary aim of this pilot study was to investigate the prevalence and characteristics of illicit substances in violent fatalities (homicides, suicides, and accidents) of the Salt River mortuary in Cape Town, South Africa. The objectives were to conduct a comprehensive drug toxicology analysis to generate qualitative and comparative data from the aforementioned cases. In addition, this study investigated the dynamics between psychoactive substance use and violent deaths in terms of toxicological trends, and the demographics and circumstances of death of the victim. Lastly, the author discusses potential qualitative associations between illicit substances and violence-related deaths in a South African setting, and provide suggestions for future toxicological analyses in these fatalities.

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13

Alfazil, Abdulkareem Abdulwahab. "Stability of drugs and pesticides of forensic toxicological interest and their metabolites in biological samples." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/1309/.

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Loss of analyte from biological samples during the post-mortem interval or during storage has potentially serious implications in forensic toxicology and represents a challenge for the forensic toxicologist, especially in the interpretation of case results. The initial aim of the studies in this thesis was to evaluate the stability of some important drugs and compounds in blood under different storage conditions in order to optimize the preservation of these compounds. A second aim was to evaluate a new method of stabilizing these compounds in blood by storing them as dried blood spots on filter paper. The third aim was to investigate methods by which corrections could be made for analyte losses based on quantification of their degradation products, which would serve as markers of the former presence of the compounds even if they were no longer detectable. The background to toxicology and its classification systems is reviewed along with the most common areas of application, including forensic toxicology. Details are given of the most commonly-used matrices and of current problems facing forensic toxicologists, particularly the problem of analyte instability. The literature concerning stability of drugs and pesticides in biological samples are reviewed and discussed as well as methods applied to enhance and stabilize analytes for long storage periods. Background is provided on methodologies used in the work reported in this thesis, including extraction techniques and instrumental analysis by LC-MS/MS and GC/MS. Also, because of its importance in forensic toxicology at present validation procedures and requirements are also discussed. An initial study was made of drug stability during storage in blood samples for 1 year under conventional laboratory conditions using selected drugs from the benzodiazepine group, alprazolam, lorazepam, oxazepam and estazolam. Blank blood containing these drugs at low and high concentrations was stored in tubes at -20° C, 4°C and room temperature. Half of the tubes contained fluoride-oxalate preservative. Blood samples were analysed on the first (day zero), second and fourth days, and after one week, two weeks, one month, two months, three months, six months and one year using a method which was developed and validated for this study based on solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Alprazolam and estazolam were stable at -20° C and 4° C, but decreased by almost 10% at room temperature (RT) at both concentrations. Lorazepam and oxazepam were stable at 20°C but were poorly stable at 4° C and decreased by 100% at RT by the end of the 1 year period. Sodium fluoride stabilised the drugs by approximately 13% compared to unpreserved samples. The long-term stability of alprazolam and estazolam is attributed to the presence of the trizolo ring in their structures which makes the compounds more resistant to hydrolysis, the most prominent degradation reaction affecting benzodiazepines. A similar study was performed on the stability of morphine-3- and 6-glucuronide and codeine-6-glucuronide in blood and urine under the same storage conditions. These compounds were stable at -20° C, losing less than 7% but losses were higher at 4° C, up to 18% in blood and 28% in urine, and at room temperature up to 54% in blood and 78% in urine after 1 year. Sodium fluoride did not have a significant effect (<10% increase in stability). An investigation was carried out on stabilisation of hydrolytically-labile benzodiazepines and cocaine in blood during storage as dried blood spots (DBS) on filter paper. An analytical method was developed and validated for this study based on SPE and LC-MS/MS analysis. The drugs selected were flunitrazepam, temazepam, oxazepam, lorazepam, nitrazepam, diazepam and cocaine. Blood spots (100 µl blood) on Guthrie card 903 containing the drugs at 1000ng/ml were dried overnight at RT. Spots were cut out and extracted with buffer (pH 6), which was analysed with the validated method. DBS were stored in duplicate at RT, 4°C and -20°C for up to one year. Degradation of the drugs in DBS in all storage conditions was less than for the corresponding liquid blood samples stored under similar conditions. More than 80% of each analyte could be recovered from DBS after one month while 15 % cocaine and 74 % of the benzodiazepines were recovered after 1 year under all conditions. The degradation of diazepam, temazepam, chlorodiazepoxide and oxazepam by hydrolysis was studied over a 1 month period under conditions designed to accelerate the reaction (80 °C, pH 2 and 12) and the hydrolysis products 2-methylamino 5-chlorobenzophenone (MACB) and 2-amino 5-chlorobenzophenone (ACB) were analysed by a method based on SPE and LC-MS/MS which was developed and validated for this study. MACB and ACB in whole blood and urine were evaluated as indicators of the original drug concentrations. Blank blood and urine containing these compounds at 1000 ng/ml stored at high temperature (80°C) and under acidic (pH 2) and basic (pH 12) conditions at room temperature for one month. The samples were analyzed in duplicate at days 1, 2, 4, 7, 14 and 30. MACB and ACB were the main hydrolysis products and their concentrations increased as degradation of the drugs proceeded. They could be detected when the starting materials had completely disappeared. However, MACB and ACB were found to be further degraded under some of the conditions used and a further study was made of the conversion of MACB to ACB. It was concluded that the drugs studied were more sensitive to alkaline pH than to acidic pH or high temperature and that MACB and ACB can be used to confirm the original presence of these drugs in samples, especially when they have decomposed due to poor or prolonged storage conditions. A final study was made of organophosphates (OPs) and their dialkylphosphate (DAP) hydrolysis products. A new method was developed and validated for analysis of OPs and DAPs in blood samples based on SPE and GCMS after derivatization with N-tert-butyldimethylsilyl-N-methyltrifluroacetamide. The influence of sodium fluoride preservative and storage as DBS on filter paper on the stability of OPs in blood was assessed over a 3 day period at RT. With preservative, DAPs concentrations increased as degradation of the OPs proceeded and they could be detected when the parent compounds had completely disappeared. OPs in DBS showed good stability in comparison to liquid blood samples containing NAF and the parent compounds were detected at the end of the observation period. It was concluded that careful attention should be given to the storage of samples to avoid loss of analyte and erroneous interpretation of results. DBS could be an effective and inexpensive way of increasing analyte retention but routine use of preservatives without evaluation of their effects is discouraged, as these may accelerate loss of analyte.

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Battah, Abdel-Kader Hamdi. "The analysis of drugs and solvents in forensic toxicology by combined GC- and LC-MS." Thesis, University of Glasgow, 1989. http://theses.gla.ac.uk/4115/.

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The work described in this thesis was in the field of Forensic Toxicology, which is the study and practice of toxicology for legal purposes. Three different application areas were considered: (a) the analysis of drugs in blood by gas chromatography-mass spectrometry (GC-MS) following isolation from the biological matrix by solid phase extraction procedures, (b) the analysis of paint solvents in blood by gas chromatography (GC) and GC-MS following dynamic headspace elution from blood, and (c) an evaluation of Thermospray/Plasmaspray (TSP/PSP LC-MS) liquid chromatography-mass spectrometry as the basis of drug screening techniques in forensic toxicology. (a) In the first of these areas, a sensitive, specific and reliable method was developed for the analysis of basic drugs in blood, using morphine and buprenorphine as model compounds which are also drugs commonly abused in the Glasgow area. A novel extraction procedure was used, based on a commercially available chemically-modified silica containing surface-bound benzenesulphonylpropyl groups, which served as a cation exchange resin. Several methods for the initial treatment of the biological matrix wre examined and the one selected involved absorption of the blood sample on diatomaceous earth and solvent elution of the crude extract containing any drugs present in the sample. This extract was then purified using the cation exchange resin: conditions suitable for the efficient retention of basic drugs and subsequent elution were also examined and developed. The extraction efficiencies for morphine were 925% and 954% at concentrations of 35 and 560ng/ml blood, respectively, for buprenorphine 836% and 875% , at concentration of 0.5 and 8ng/ml respectively, and for other drugs were better than 85% . The end-step analytical technique chosen for this method was GC-MS, because of analytical and legal requirements with respect to sensitivity and specificity. The polar nature of the model compounds, and of many other drugs likely to be encountered in this field, required chemical modification of the substances prior to gas chromatography. A comparison was made of three silyl ether derivatives - the trimethylsily (TMS), ethyldimethylsilyl (EMS) and tert-butyldimethylsilyl (MTBS) ethers. The conditions required for derivative formation were examined, including the choice of silyl donor reagent, solvents, temperature of reaction and time to completion. The EDMS donor, diethyltetramethyldisilazane, was selected on the basis of the midl reaction conditions required for the test compounds and also because this reagent caused less interference during GC-MS analysis. EDMS ethers gave satisfactory gas chromatographic behaviour and the presence of prominent ions at high mass was shown to be advantageous for specific and sensitive detection by SIR-MS with little background interference. The developed method was considered to be useful for both clinical and post-mortem blood samples containing morphine and buprenorphine down to the low picogram/millilitre level, and therefore adequate for the intended purpose. The method was subsequently applied to 13 samples submitted for analysis to the Department of Forensic Medicine and Science and found to be satisfactory. (b) In the second area of application, dynamic head space (DHS) elution was used for the analysis of paint solvents in blood. Volatilised solvents were trapped on a Tenax-GC cartridge and were subsequently analysed by GC-MS. The extraction efficiency of this method for C18-C12 n-alkane hydrocarbons, which were present in the paint materials, was better than 90% and sensitivity down to pg/ml levels was obtained. Solvent extraction procedures for these hydrocarbons were evaluated using high purity solvent. The extraction efficiency was better than 85% . Analysis of extracts by GC or GC-MS suffered from interference from the solvent front which reduced the sensitivity. The DHS method was applied to a pilot study for occupational monitoring of a group of painters to assess the presence of paint solvents in their blood. Two venous blood samples were collected at the beginning and at the end of a working week from each subject. They showed the presence of several solvents similar to those present in paint material and the levels in the second series of samples were higher than those of the first series. The differences between the levels in the two series were statistically significant for n-nonane, n-undecane and alkylbenzenes. The levels in the first sample indicated incomplete clearance of these solvents from the body during the weekend, and the second samples indicated solvent uptake during the working week. Solvent contamination in the extraction system was tackled by several approaches but still hindered the accurate estimation of solvent levels in blood. (c) In the third area of application, the operating parameters which control the sensitivity of the mass spectrometer using the TSP/PSP LC-MS interface were evaluated. These included the effects of the probe temperature and discharge voltage on sensitivity and mass spectral fragmentation pattern and the effects of the mobile phase constituents on sensitivity and mass spectral peak stability. Solvent systems containing ammonium acetate buffer and an organic modifier such as acetonitrile produced the best results in plasmaspray LC-MS. Three model HPLC-MS analyses were developed for mixtures of basic drugs, barbiturates and opiates using both the plasmaspray positive and negative ion modes. During the development of the mobile phases, the optimization of chromatography by organic modifiers was assessed. The quality of chromatography obtained was not always as good as expected in conventional HPLC, but the combination of chromatographic and mass spectral data could be used for identification and quantification purposes. A compilation of PSP mass spectra of drugs commonly encountered in forensic toxicology was produced. These mass spectra provided mostly molecular weight information with little structural information.

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15

Cooper, Gail Audrey Ann. "Application of solid-phase extraction for the analysis of drugs in biological matrices." Thesis, University of Glasgow, 1999. http://theses.gla.ac.uk/5368/.

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Experimental mixed-mode solid-phase extraction columns of differing carbon number and carbon loading were investigated for the efficient extraction of drugs of abuse from biological matrices. Methadone and its two major metabolites (EDDP and EMDP) were chosen due to the increase in methadone drug-related deaths in the West of Scotland. Amphetamine and related compounds (methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methyleneidoxymethamphetamine (MDMA) and 3,4-methylenedioxyethylamphetamine (MDEA)) were chosen because of the prevalence of use of "speed" and "ecstasy" throughout the United Kingdom and the challenge these volatile drugs pose to the analyst. Improved methods were developed for the efficient extraction of methadone, EDDP and EMDP from whole blood and for amphetamine and related compounds from whole blood and hair. These methods were successfully applied to the analysis of postmortem samples. The stability of methadone, EDDP and EMDP in whole blood was investigated using the developed extraction method after sorting at various temperatures for a period of six months. Methadone remained stable in blood after six months. This was confirmed by the analysis of postmortem cases samples which when re-analysed within six months of the initial analysis, correlated well. Postmortem hair samples proved useful for determining antecedent drug use history whether extracted by solid-phase extraction or after screening with a Cohort enzyme immunoassay kit, adapted for hair analysis. Solid-phase extraction provides a clean and efficient means of extracting drugs of abuse from whole blood and hair. Simple manipulation of the extraction system (sample pretreatment, pH, derivatisation) provides a versatile alternative to lengthy liquid-liquid extraction techniques and has the added potential of automation.

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Benson, Andrew James. "High-performance liquid chromatography (HPLC) and high-performance liquid chromatography mass spectrometry (HPLC/MS) for the analysis of date rape drugs." FIU Digital Commons, 2002. http://digitalcommons.fiu.edu/etd/1602.

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The drugs studied in this work have been reportedly used to commit drug-facilitated sexual assault (DFSA), commonly known as "date rape". Detection of the drugs was performed using high-performance liquid chromatography with ultraviolet detection (HPLC/UV) and identified with high performance-liquid chromatography mass spectrometry (HPLC/MS) using selected ion monitoring (SIM). The objective of this study was to develop a single HPLC method for the simultaneous detection, identification and quantitation of these drugs. The following drugs were simultaneously analyzed: Gamma-hydroxybutyrate (GHB), scopolamine, lysergic acid diethylamide, ketamine, flunitrazepam, and diphenhydramine. The results showed increased sensitivity with electrospray (ES) ionization versus atmospheric pressure chemical ionization (APCI) using HPLC/MS. HPLC/ES/MS was approximately six times more sensitive than HPLC/APCI/MS and about fifty times more sensitive than HPLC/UV. A limit of detection (LOD) of 100 ppb was achieved for drug analysis using this method. The average linear regression coefficient of correlation squared (r2) was 0.933 for HPLC/UV and 0.998 for HPLC/ES/MS. The detection limits achieved by this method allowed for the detection of drug dosages used in beverage tampering. This method can be used to screen beverages suspected of drug tampering. The results of this study demonstrated that solid phase microextraction (SPME) did not improve sensitivity as an extraction technique when compared to direct injections of the drug standards.

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17

Al-Asmari, Ahmed Ibrahim. "Applications of LC-MS/MS in forensic toxicology for the analysis of drugs and their metabolites." Thesis, University of Glasgow, 2009. http://theses.gla.ac.uk/1290/.

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This thesis studied opioids and alcohol in forensic toxicology by LC-MS/MS, which avoids time-consuming procedures involving hydrolysis, extraction and derivatisation. Initially, a method was validated for quantification of opioids and unhydrolysed polar metabolites in autopsy specimens and was used to develop procedures for interpretation of forensic toxicology results. The LC-MS/MS method developed has been validated for the simultaneous determination of 24 opioids in human whole blood, including, for the first time in human whole blood, naloxone-3-glucuronide. Although a large number of drugs of interest were included in the method, acceptance criteria for linearity, precision, and recovery for all analytes were achieved. The method was found useful for differentiating between users of heroin and other opioids, such as codeine and morphine, and for determining the survival time in deaths attributed to heroin use. Subsequently, the efficiencies of hydrolytic and non-hydrolytic methods for opioid analysis were compared for buprenorphine (BUP) analysis. The aims were to develop and validate a method for the direct determination (DM) of buprenorphine (BUP), norbuprenorphine (NBUB), buprenorphine-3-glucuronide (B3G) and norbuprenorphine-3-glucuronide (NBUP3G). This method was compared with an in house enzymatic hydrolysis method (HM) for the determination of total buprenorphine (TBUP) and norbuprenorphine (TNBUP), using real positive BUP urine case samples. A comparison between the drug and metabolite concentrations obtained by direct and hydrolysis methods was reported for the first time in this work. LC-MS analysis was also applied to paediatric plasma specimens obtained from a clinical pharmacokinetic study of intravenous and intranasal administration of diamorphine. This work was aimed at obtaining pharmacokinetic data for diamorphine and its metabolites in children following intravenous (IVDIM) and intranasal (INDIM) administration in a blind study. It was intended that the concentrations of active metabolites would be used to evaluate whether or not IN-DIM can deliver rapid and efficient analgesia in children comparable to that obtained with IV-DIM. The pharmacokinetics of DIM and its metabolites following INDIM and IVDIM administration in children have been compared for the first time in this study, which confirmed that INDIM can achieve therapeutic plasma concentrations of active metabolites, although these were lower than those obtained with IVDIM and occur at later times after administration. In Scotland, the number of prescriptions for oxycodone has risen by 430% since prescribing began in 2002. Blood samples from fatalities in the West of Scotland involving oxycodone were analysed using an LC-ESI-MS/MS method developed for the determination of oxycodone and its metabolites in post-mortem specimens. To the author’s knowledge, this is the first report of blood and urine concentrations of noroxycodone and oxymorphone in acute oxycodone overdoses. Also, it is the first LC-MS/MS application to be reported with oxycodone related fatalities cases in forensic toxicology as most of previous reports used GC or HPLC applications. Moreover, this work reported for the first time vitreous humour levels of noroxycodone following oxycodone intoxication. Ten oxycodone-related deaths were identified in the short period of this study in the Strathclyde region of Scotland alone, highlighting the importance of including this drug in routine laboratory screening and confirmation procedures. Polar alcohol metabolites ethyl glucuronide and ethyl sulfate are biomarkers of ante-mortem alcohol consumption and are used to test for post-mortem artefactual formation of alcohol. An LC-MS method for these metabolites using a novel hydrophilic interaction liquid chromatography column was validated and applied to routine forensic casework. Ninety urine case samples were divided into three groups depending on the ethanol concentration found in blood and analysed by the developed method: group A with post-mortem blood ethanol higher than 200 mg/100 mL; group B with ethanol concentration in the range 80 to 200 mg/100 mL and group C with ethanol concentration less than 80 mg/100 mL. It was concluded that the risk of false positive ethanol results increased in the low ethanol concentration group as several cases tested negative for both biomarkers. ETG was detected at low concentrations in some cases for which ETS tested negative, suggesting that either ETG may have a longer half-life in urine or else ETS is unstable. The data was compared with previous studies and confirmed that both ethanol biomarkers should be determined in heavily putrefied cases and when the ethanol level in post-mortem blood is low, suggesting the production of ethanol after death. To the authors’ knowledge, this is the first report of the determination of ETS using an LC-ESI-ion trap-MS/MS method, and of a HILIC-ESI-ion trap-MS/MS method for the simultaneous determination of ETG and ETS in post-mortem urine samples.

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Al, Jaber Jaber. "Forensic and clinical toxicology studies focusing on drug analysis in hair and other biological matrices." Thesis, Queen Mary, University of London, 2013. http://qmro.qmul.ac.uk/xmlui/handle/123456789/8507.

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Clinical and forensic toxicology analysts rely heavily in their daily tests on the analysis of the conventional samples (blood and urine). However, these specimens are limited in the time scale they reflect with regard to drug intake history and also in terms of drug stability within the matrices. Alternative matrices such as hair, oral fluids and dried blood spots (DBS) provide new horizons and new opportunities. Drugs incorporated within hair are very stable. Hair also provides a very long detection window, for at least one year, if not a lot longer. Oral fluids on the other hand are non-intrusive, easy to collect and much cleaner sample matrix than blood or urine. DBS also offer great drug stability, are easy to collect, faster to analyse and suitable for automated analysis. However, a number of studies are needed to assess the limits of these alternative samples in terms of the correlation of their results with the results of conventional samples and with regard to drug stability. Such studies will enable a more reliable and confident interpretation of results obtained from these matrices especially for medico-legal purposes. The main aims of this research were: to develop and validate analytical methods for detection and quantitation of drugs of use and abuse in hair, oral fluids, blood and DBS samples, to investigate the correlation between dose and drug concentration in hair, blood and oral fluids after controlled chronic drug administration, to investigate the stability of anti-psychotic drugs in DBS (from patients) stored under different conditions and the effect of addition of preservative, and to investigate the alcohol intake prevalence among Kuwaiti drug addicts and correlate these results with selfreported intake. As the majority of drugs were basic, an extraction method based on methanolic incubation was developed for detection of basic/weak basic drugs in hair. It was compared to alkaline digestion (with NaOH) followed by liquid-liquid extraction (LLE). Detection was achieved by LC-MS/MS (Sciex2000) after separation on a C18 column. When applying both methods on positive authentic hair samples the results showed that the methanolic method was capable of extracting most basic drugs in hair but only partially, while the alkaline digestion method was found to degrade V some unstable drugs like sulpiride, but was capable of fully extracting the alkaline stable drugs such as quetiapine. After development and validation of the LLE-LC-MS(Exactive) method for the analysis of anti-psychotics in blood, oral fluids and hair, an investigation was carried out on the correlation pattern between trough concentrations in those three matrices. The most significant correlation coefficients (r) found were those between blood and hair concentrations, procyclidine r=0.83 (18 subjects p=<0.001), risperidone r=0.96 (14 subjects p=<0.001), haloperidol r=0.90 (10 subjects p=<0.001), OH-risperidone r=0.24 (13 subjects p=>0.44), quetiapine r=0.28 (14 subjects p=>0.33) and chlorprothixene r=0.32 (13 subjects p=>0.32). Among the interesting results was the strong correlation found between drugs half-lives and the mean ratio of hair concentration/dose (r=0.96, p=<0.003). The stability of anti-pyschotics in DBS from patients’ samples was assessed by storing them at four different temperatures (25, 4, -20 and -80°C) with and without prior impregnation of the DBS cards with sodium fluoride. After development and validation of the LLE-LC-MS method, samples were analysed at days 0, 45, 90 and 180. Results showed good stability of all the compounds (procyclidine, quetiapine, risperidone, OH-risperidone, chlorprothixene and haloperidol) in all the different storage conditions and no significant increase or decrease in drug concentrations with sodium fluoride impregnation. Finally, after trials with five different HPLC columns, two SPE cartridges, two LLE extraction procedures and two mass spectrometer instruments, a method was developed and validated for the detection and quantitation of alcohol’s minor and specific metabolite in hair, ethyl glucuronide (EtG). The method has a limit of detection (LOD) of 3pg/mg and lower limit of quantitation (LLOQ) of 9pg/mg. This method was applied to 59 hair samples from patients at a general addiction centre and alcohol prevalence was investigated and its correlation with self-reported use was investigated.

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19

Bishop, Sandra Charlotte. "Advanced capillary electrophoretic techniques for the detection of date-rape and club drugs for a forensic setting." Ohio : Ohio University, 2004. http://www.ohiolink.edu/etd/view.cgi?ohiou1107528810.

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20

Bishop, Sandra Charlotte. "Advanced Capillary Electophoretic Techniques for the Detection of Date-Rape and Club Drugs for a Forensic Setting." Ohio University / OhioLINK, 2004. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1107528810.

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21

Scott, Karen S. "An evaluation of the use of supercritical fluid extraction techniques to recover drugs from biological matrices." Thesis, University of Glasgow, 1998. http://theses.gla.ac.uk/3460/.

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The use of supercritical fluid extraction (SFE) was evaluated for the determination of drugs of Forensic interest. Three matrices were investigated. The first two (blood and vitreous humor) were compared to SPE and LLE methodology currently in use at the Department of Forensic Science and Medicine. The third matrix, hair, was assessed to determine its usefulness as a marker of past drug use. Three types of drugs were investigated by SFE namely, Benzodiazepines, morphine and methadone. Successful methodology was developed for all three matrices and all three drug types, providing an efficient, reproducible alternative method to SPE and LLE, which reduced the environmental risks from organic solvents. The developed methods were applied to the analysis of authentic forensic samples. In addition to comparing well with the results obtained with the conventional techniques, good correlation was obtained between blood and vitreous humor results for temazepam, diazepam, methadone and morphine. Thus, in cases where a body is badly decomposed or burned, vitreous humor can be used as an alternative post-mortem sample. In addition to the determination of morphine, 6-monoacetyl morphine (6MAM) was used as marker of heroin abuse. 6MAM was detected in all three samples matrices, thus confirming the use of heroin prior to death. Hair analysis for all three types of drugs was carried out using a single extraction method. A wide range of concentrations was found for all drug types. As with blood and vitreous humor, 6MAM was detected and used as a marker of heroin abuse. From this, 61% of known heroin users were confirmed.

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22

Curtis, Byron Dale. "The forensic toxicology of 2,5-dimethoxy-4-n-propylthiophenethylamine (2C-T-7)." Oklahoma City : [s.n.], 2005.

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23

Korb, Ann-Sophie. "Drugs of abuse in oral fluid and endogenous post-mortem blood concentrations of gamma-hydroxybutyrate." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/8696/.

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Oral fluid is a versatile matrix that is proving more popular within forensic toxicology. Its use is multifaceted, and is the preferred matrix in therapeutic drug monitoring and roadside testing of drivers suspected to be under the influence of drugs. Benefits including the difficulty of adulteration, the ease and non-invasiveness of sample collection, the range of analytes that can be detected and decent correlations between concentrations in blood or plasma and oral fluid are some of the reasons for its attractiveness to practitioners and forensic toxicologists. Most often, oral fluid is collected using collection devices which can often include a stabilising buffer. When new collection devices are introduced to the market it is important that their applicability to drug testing is investigated to show they are fit for purpose. One of the newest collection devices on the market is the NeoSAL™ collection device from Neogen. This collector was gravimetrically assessed for oral fluid volume collection and drug recovery. Collection volume adequacy of the NeoSAL™ device was compared to two commonly used, commercially available, collection devices: namely the Immunalysis Quantisal™ and the OraSure Intercept® i2™ collection devices. Results showed that the NeoSAL™ device is capable of collecting more than the volume stated by the manufacturer, similar to the Intercept® i2™ which also over-collected, whereas the Quanitsal™ device collected the stated volume. Drug recoveries from the NeoSAL™ collection pad for all drugs investigated in this thesis exceeded 57% (lower recoveries were observed for temazepam and diazepam). Although amphetamine and methamphetamines are not often abused or encountered in forensic samples in Scotland, they are a global problem and effects of abuse can negatively impact a person’s ability to drive by increasing recklessness and risk-taking. Neat and oral fluid collected using the NeoSAL™ device were used to develop and partially validate a method for the quantification of amphetamine, methamphetamine, MDMA, MDA and MDEA using GC-MS. MDEA was also assessed, but did not give acceptable results for accuracy and precision. A short-term autosampler stability study for the four acceptable analytes showed that they were stable on the autosampler for up to 48 hours (~ 19 °C). Opioid and benzodiazepine drugs are two of the most commonly abused drug groups in Scotland. They are often taken synchronously, and the latter is the most commonly prescribed and encountered drug group in Scotland. With the continuation of opioid epidemics and large numbers of people in opioid-treatment programmes, it is beneficial to have a sensitive and selective method that can be used for the simultaneous analysis of these two drug groups. Research has shown that both drug groups are common in drivers, although symptoms of use include loss of coordination, sedation, and drowsiness. An SPE procedure using LC-MS/MS detection was optimised for the extraction for the concurrent analysis of 5 benzodiazepines and 5 opioid drugs. The method was validated according to the guidelines for method validation in forensic toxicology (SWGTOX 2013). The validated method was successfully applied to paired oral fluid and blood samples collected from 16 benzodiazepine users. The NeoSAL™ collection device showed that good recoveries (>57% for all analytes but diazepam and temazepam), and good detection rates for the 10 analytes studied was possible. Oral fluid and blood results showed a good correlation between the analytes detected and in most cases where there was no overlap, it was possible to explain these discrepancies by metabolism, detection windows, low sample volume, and sensitivities of the respective analytical methods used. Gamma-hydroxybutyrate (GHB) is a short-chain fatty acid that is not only endogenous to the mammalian body, but can also be prescribed medicinally and be used as a drug of abuse. A stability study (over 56 days) of GHB in neat oral fluid was carried out as none have been published in the literature. GHB stability is an important factor to assess due to its short detection window in the more traditional matrices blood and urine. A simple protein precipitation extraction procedure was used, and the analytical GC-MS method was adapted from the in-house method for analysis of GHB/beta-hydroxybutyrate (BHB) in blood. The method was partially validated and the stability of GHB was assessed at two concentrations at three temperatures (fridge ~ 4 °C, freezer ~ -21 °C, and room temperature ~ 20 °C). GHB appeared to be stable at all three temperatures for up to 56 days. Endogenous post-mortem blood concentrations of GHB have been widely studied, however debate is still existent regarding cut-off concentrations that should be applied. Problematic interpretation arises from the post-mortem production, and inter- and intra- individual variation of GHB in the human body. 1811 cases between 2010 and 2016, which did not implicate GHB in the cause of death or where GHB was not suspected to have been used, were extracted from the in-house Forensic Medicine and Science (FMS) database. The majority of cases (51%) were deaths related to alcohol abuse. 76% of cases showed GHB concentrations < 30 mg/L, and 94% of all cases had concentrations of less than 50 mg/L. Results also suggest that the use of a preservative may prevent in vitro formation of post-mortem GHB. 112 cases showed GHB concentrations in excess of 50 mg/L with advanced decomposition, therefore suggesting that decomposition changes may increase GHB concentrations. This was the largest dataset that ever studied endogenous post-mortem GHB concentrations, and results highlight the difficulty when applying cut-off concentrations to distinguish post-mortem or exogenous and endogenous concentrations.

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Wallace, Nicole. "Forensic Science Applications Utilizing Nanomanipulation-Coupled to Nanospray Ionization-Mass Spectrometry for the Analysis of Ultra-Trace Illicit Drugs." Thesis, University of North Texas, 2010. https://digital.library.unt.edu/ark:/67531/metadc33209/.

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Presented in this thesis are two methods that are coupled to the instrumentation for the recovery and analysis of ultra-trace illicit drug residues. The electrostatic dust lifting process is coupled with nanomanipulation-nanospray ionization to retrieve drug particles off of hard surfaces for analysis. For the second method, drug residues from fingerprint impressions are extracted followed by analysis. The methodology of these hyphenated techniques toward forensic science applications is applied as to explore limits of detection, sensitivity, and selectivity of analytes as well as immediacy and efficiency of analysis. The application of nanomanipulation-coupled to nanospray ionization-mass spectrometry toward forensic science based applications is considered as future improvements to trace and ultra-trace analysis.

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Pereira, Carlos Victor Montefusco. "Assessment of neuronal cytotoxicity of JWH-073 and JWH-250." Master's thesis, Instituto Superior de Ciências da Saúde Egas Moniz, 2014. http://hdl.handle.net/10400.26/6715.

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Dissertação de Erasmus Mundus para obtenção do grau de mestre em Técnicas Laboratoriais Forenses
Synthetic cannabinoids from marijuana herbal blends like ‘Spice’ and ‘K2’ are drawing the attention of drug of abuse organizations, including the UNODC1, the EMCCDA2 and emergency hospital all over the world. This concern rises from clinical episodes of psychotropic effects that go beyond the regular range of marijuana and THC – namely, panic attacks, psychosis, catatonia, addiction and withdrawal symptoms. Our study addressed two emergent synthetic cannabinoids (napthtoylindoles) denominated JWH-073 and JWH-250 that are currently detected on ‘Spice’-like products, in order to observe their cell toxicity profile on neuronal cells in vitro model (SH-SY5Y). Using 0.2% DMSO as negative control, MTT and LDH results revealed that within concentrations of 1, 5, 10, 25, 37.5 and 50 μM, JWH-250 is identified as ‘toxic’ in a statistically significant manner at higher concentrations. This work did not detect any statistically significant toxicity from JWH-073. This data suggests to extend these studies on new synthetic cannabinoids to neuronal cells with increased concentrations, as well as the application of assays assessing apoptosis (conditions and signalling), neuronal function and activity (as cell membrane potential assay) within differentiated cells as neurons and glia. At the same time, the evaluation of herbal mixtures of more than one cannabinoids and plant types is advisable in order to understand synergic effects.
EACEA - European Commission

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26

Deeb, Shaza. "Determination of antiepileptic drugs in biological matrices by LC/MS/MS with a focus on their role in forensic cases." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7159/.

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Antiepileptic drugs (AEDs) are prescription only medications which were firstly introduced in the 1880s to treat epilepsy. However, the rapid growth in the drug discovery market led to a new generation of AEDs with multiple mechanisms of action. These new drugs represent a promising treatment for many diseases in addition to epilepsy such as neurological disorders, psychological disorders and substance and alcohol abuse treatment as substitutes for benzodiazepines and methadone. However, their multiple roles triggered their misuse potential and concern on their abuse potential was raised in the literature, the media, and by many addiction organizations. Hence, this research highlights some of the AEDs which have raised concern and discusses their therapeutic effects, mechanism of action as well as their overdose and abuse probability from a forensic toxicology point of view. Some AEDs have a narrow therapeutic index and require therapeutic drug monitoring in order to attain the optimum response. The majority of published analytical methods focuses on their analysis in serum and plasma within therapeutic ranges and includes a maximum of 11 AEDs in one analytical step. Therefore, a robust and accurate method was developed for the simultaneous analysis of 15 common AEDs and two of their major metabolites in whole blood using LC/MS/MS. The method was validated according to the standard practices for method validation in forensic toxicology (SWGTOX, May 2013) over a wide concentration range to include AED therapeutic and toxic concentrations which make it suitable for both clinical and forensic analysis. Stability studies are of great importance in forensic cases where it takes up to a few weeks for autopsy, sampling, drug screening and finally confirmation analysis. However, reports specifically addressing the stability of antiepileptic drugs in whole blood are relatively scarce compared with those for drugs of abuse. Thus, using the previous method, the stability of AEDs in whole blood was investigated under different storage conditions. The LC/MS/MS method developed for AEDs analysis in whole blood was successfully transferred to another laboratory and extended to include 18 AEDs and 4 metabolites. It was revalidated for AEDs analysis in serum and plasma in addition to whole blood. Before any new method can be adapted to routine forensic analysis, it has to be validated using authentic samples. A total of 467 previously processed samples were reanalysed using the transferred method. The results were compared to the reference laboratory's values and these showed a very good correlation. The prevalence of AED abuse, namely gabapentin and pregabalin, was investigated among prisoners. 904 urine samples were collected from 8 prisons in Scotland over a one month period. Firstly, a simple and accurate method was developed and qualitatively validated for 21 AEDs in urine to screen the urine samples. Secondly, the method was quantitatively validated for the positive AEDs. Drug analysis in hair has multiple applications in clinical laboratories and forensic toxicology. However, only a few papers have considered conventional AEDs analysis in hair for therapeutic drug monitoring purposes. As part of this research, AED extraction from hair samples was investigated. Six different digestion methods and 4 clean-up procedures were compared for 16 AEDs. An LC/MS/MS method was qualitatively validated using the extraction procedure that attained the highest recovery with all AEDs. Subsequently, two authentic hair samples were tested and the method was quantitatively validated for the positive AEDs in these samples.

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McBride, Ethan. "Utilizing Rapid Mass Spectrometry Techniques to Profile Illicit Drugs from Start to Finish." Thesis, University of North Texas, 2018. https://digital.library.unt.edu/ark:/67531/metadc1248455/.

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The increasingly complex world of illicit chemistry has created a need for rapid, selective means of determining the threat posed by new drugs as they are encountered by law enforcement personnel. To streamline this process, the entirety of the problem, from the production of illicit drugs all the way to the final analysis have been investigated. A series of N-alkylated phenethylamine analogues were synthesized in a shotgun method and subjected to direct-infusion analysis. A range of products were detected without the need for time-consuming purification steps, which was extended to novel pharmacological and receptor-binding assays where mass spectrometry is used as a detector. This direct-infusion technique was also applied to studies of methamphetamine and fentanyl production to preemptively determine improvements to common reaction conditions and explore the origins of common impurities. The ability to utilize these rapid techniques directly from the fume hood has also been critically reviewed to highlight gaps in current research and opportunities for improvement. When combined, these studies seek to provide a means for rapid, simplified analysis of illicit drugs to improve the quality of data and dramatically increase throughput.

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Muccio, Zeland. "Isotope ratio mass spectrometry a rapidly developing tool for forensic samples /." Ohio : Ohio University, 2010. http://www.ohiolink.edu/etd/view.cgi?ohiou1263488205.

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Leite, Flávia Pine. "Determinação de club dugs em sangue total por cromatografia líquida acoplada a espectrometria de massas com analisador híbrido quadrupolo-tempo de voo (LC-QTOF-MS)." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-11062018-110009/.

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As chamadas club drugs compreendem um vasto grupo de substâncias frequentemente utilizadas em bares, festas e raves, com a finalidade de intensificar o contato social e a estimulação sensorial. Englobam desde substâncias sintéticas comumente conhecidas, como a anfetamina, a metanfetamina, o MDMA, até moléculas de surgimento mais recente, denominadas novas substâncias psicoativas. Isoladas ou associadas a outras drogas, é possível que sejam causa de morte per se, ou que predisponham o usuário a envolver-se em situações potencialmente fatais, sendo necessário que os órgãos de Perícia Criminal (Institutos Médico Legais e Institutos de Criminalística) estejam aptos a detectar e quantificar essas substâncias em amostras biológicas. O presente trabalho teve como objetivo desenvolver um método analítico para identificação e quantificação de club drugs em sangue total, utilizando cromatografia líquida acoplada a espectrometria de massas com analisador híbrido quadrupolotempo de voo (LC-QTOF). Após o desenvolvimento do método, este foi validado utilizando as diretrizes do guia de validação do Scientific Working Group for Forensic Toxicology (SWGTOX), sendo analisados de linearidade, limite de detecção, limite de quantificação, efeito matriz, precisão intradia, precisão interdia, exatidão e integridade de diluição, além de recuperação e eficiência do processo. O método desenvolvido compreendeu a determinação de MDA, MDMA, 2C-B, DOB, cetamina, mCPP, cocaína e cocaetileno. Amostras provenientes de casos reais de morte não natural, oriundas do Instituto Médico Legal Aristoclides Teixeira de Goiânia - GO foram analisadas pelo método desenvolvido. 56 casos foram selecionados, em sua maioria com histórico de morte por projétil de arma de fogo e acidente de transito. Das 56 amostras analisadas, 28,5% (n=16) foram positivas para cocaína e/ou cocaetileno. As demais substâncias pesquisadas não foram encontradas nas amostras.
Club drugs are a large group of substances consumed in pubs, parties and raves, aiming to intensify social contact and sensorial stimulation. The term comprises largely known substances such as amphetamine, methamphetamine, 3,4-methylenodioxymethamphetamine (MDMA), as well as so-called new psychoactive substances, which are synthetic drugs recently developed or recently introduced in drug market. Club drugs can be taken alone, combined with each other or, most frequently, with alcohol or other commonly abused drugs such as cocaine. In any of these situations, club drugs can possibly be the cause of death or potentialize the involvement of the user with crime and potentially fatal behavior. Thus, official organisms in charge of criminal investigation must be capable of identifying and quantifying these substances in biological samples. The present work aimed the development of an analytical method to identify and quantify club drugs in whole blood, using liquid chromatography - mass spectrometry with hybrid analyzer quadrupole - time of flight (LC-QTOF). After analytical development, the method was validated according to do Scientific Working Group for Forensic Toxicology (SWGTOX) guidelines, evaluating linearity, limit of detection, limit of quantification, matrix effect, precision, intermediate precision, bias and dilution integrity, besides recovery and process efficiency. The developed method comprised MDA, MDMA, 2C-B, DOB, ketamine, mCPP, cocaine and cocaethylene determination. Real samples related to non-natural deaths were collected at Institute of the Legal Medicine Aristoclides Teixeira, Goiânia, Goiás, Brazil, and analyzed by the developed method. 56 cases were selected, most of them related to fire gun injury and traffic events, 28,5% (n=16) of them being positive for cocaine and/or cocaethylene. None of the other drugs comprised in the analysis were detected in these samples.

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30

Ma, Xiaofan. "The use of graphene quantum dots as detection elements in nanomaterials-based sensors for forensic applications." Thesis, KTH, Tillämpad fysik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-298092.

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The large-scale abuse and addiction of narcotics such as amphetamine and cocaine have become a global problem. In this project, we innovatively use graphene quantum dots (GQDs) as a fluorescent sensor to detect and quantify amphetamine and cocaine. This technology will have broad forensic application prospects. Compared with metallic quantum dots, graphene quantum dots are green and safe, with excellent bio-compatibility and low toxicity. We used undoped and N-doped GQDs as fluorescent sensing probes for the detection of amphetamine and cocaine, respectively. Using FTIR and FL as characterization methods, the fluorescence luminescence of GQDs under multiple excitation wavelength bands was studied and compared with the fluorescence after adding drugs. The experimental results show that the N-doped GQDs has a higher response to the binding substance. The detection concentration of amphetamine ranges from 5 µM to 5 mM, and the detection concentration of cocaine ranges from 10 µM-10 mM. Within this range, the fluorescence peak intensity ratio and the drug concentration have a two-stage linear negative correlation.
Storskaligt missbruk och missbruk av narkotika som amfetamin och kokain har blivit ett globalt problem. I detta projekt använder vi innovativt grafenkvantprickar (GQDs) som en fluorescerande sensor för att detektera och kvantifiera amfetamin och kokain. Denna teknik kommer att ha breda rättsmedicinska applikationsmöjligheter. Jämfört med traditionella kvantprickar är grafenkvantprickar gröna och säkra, med utmärkt biokompatibilitet och låg toxicitet. Vi använde odopade och N-dopade GQD: er som fluorescerande avkännande sonder för detektion av amfetamin respektive kokain. Med användning av FTIR och FL som karakteriseringsmetoder studerades fluorescens luminiscens hos GQD under flera exciteringsvåglängdsband och jämfördes med fluorescensen efter tillsats av läkemedel. De experimentella resultaten visar att den N-dopade GQD har ett högre svar på den bindande substansen. Detekteringskoncentrationen av amfetamin sträcker sig från 5 µM till 5 mM, och detektionskoncentrationen av kokain varierar från 10 µM-10 mM. Inom detta område har fluorescens toppintensitetsförhållandet och läkemedelskoncentrationen en tvåstegs linjär negativ korrelation.

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Johansson, Lars. "Teenager fatalities : epidemiology and implications for prevention." Doctoral thesis, Umeå universitet, Rättsmedicin, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-36682.

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A significant number of teenagers are killed each year by unintentional or intentional injuries. A teenager is in a vulnerable phase of her/his life, going from being a child to adult. This transition often includes testing the limits of their capabilities, which can include, e.g., high speed driving, testing alcohol and other drugs, including drinking and driving. The development from child to adult includes different psychological stress factors, such as, e.g., school problems, broken love affairs and bullying. The demands – perceived or real – also increases over time and vulnerable individuals can turn to self-harm and in the most extreme case suicide. The aim of this thesis was to investigate teenager fatalities in the northern half of Sweden and to suggest preventive measures. A survey of teenager fatalities during a twenty-year period revealed that the incidence of unintentional (n=248) deaths decreased, while intentional (n=102) deaths were unaffected over time. Most unintentional deaths were transportation related (n=204) while most of the intentional deaths were suicides (n=88). Twenty-eight percent of the decedents were test-positive for alcohol at autopsy. In a series of three studies, teenager suicides were investigated in depth, firstly through an interview study with the investigating police officer in charge of the investigation of a teenager suicide. Most of the suicides occurred in rural and depopulated areas despite the fact that most teenagers live in the larger cities along the coastline. A majority of the suicides appeared to be planned. Females, contrary to males, often had a psychiatric history. One of the conclusions was that police officers provide essential information concerning the circumstances around a teenager suicide. Parents who had lost a child through suicide, and in some cases siblings, were interviewed 15-25 months after the suicide. It was striking how the life of the surviving family members were still affected by the devastating trauma of the suicide; most parents testified that they were still struggling with the question “why?” and that they were thinking of their lost child every day. Post suicide support was often badly timed and insufficient, especially for the younger siblings. The family doctor has an important role as a co-ordinator of a long-term individually formulated support scheme for the bereaved. Evidence of suicide contagion and suicide cluster formation, i.e., one teenager suicide led to another suicide, was found in these studies, and two suicide clusters were identified, with links between the victims in each cluster. Both clusters occurred within a geographical and timely proximity. Everyone involved in the well-being of the young should be aware of the risk of contagion and suicide cluster formation. The fifth study concerned 12,812 teenagers who visited the Emergency Room at Umeå University Hospital due to an injury during 1993 through 2006. Sixty-one of these were found dead through 2007, 49 by unnatural (of which 38 were included) and 12 by natural causes. The standard mortality rate for unnatural death was calculated to 1.44 (1.02-1.98), confirming an increased risk of premature death. In many of these deaths, alcohol and drugs may have contributed. By increasing the awareness among health professionals that injury can predict a premature death - primarily among those who develop substance abuse - some premature deaths may be prevented by early intervention. This thesis confirms that most teenagers die from unnatural causes, mostly in transportation-related events and by suicide. By studying these deaths, preventive measures that could save lives have been suggested.

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Mitheo, Yannick K. "Determination of Solute Descriptors for Illicit Drugs Using Gas Chromatographic Retention Data and Abraham Solvation Model." Thesis, University of North Texas, 2015. https://digital.library.unt.edu/ark:/67531/metadc804935/.

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In this experiment, more than one hundred volatile organic compounds were analyzed with the gas chromatograph. Six capillary columns ZB wax plus, ZB 35, TR1MS, TR5, TG5MS and TG1301MS with different polarities have been used for separation of compounds and illicit drugs. The Abraham solvation model has five solute descriptors. The solute descriptors are E, S, A, B, L (or V). Based on the six stationary phases, six equations were constructed as a training set for each of the six columns. The six equations served to calculate the solute descriptors for a set of illicit drugs. Drugs studied are nicotine (S= 0.870, A= 0.000, B= 1.073), oxycodone(S= 2.564. A= 0.286, B= 1.706), methamphetamine (S= 0.297, A= 1.570, B= 1.009), heroin (S=2.224, A= 0.000, B= 2.136) and ketamine (S= 1.005, A= 0.000, B= 1.126). The solute property of Abraham solvation model is represented as a logarithm of retention time, thus the logarithm of experimental and calculated retention times is compared.

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Santos, Júnior Júlio César 1985. "Novas técnicas analíticas aplicadas a drogas de abuso presentes em humor vítreo." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/312948.

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Orientadores: Nelci Fenalti Höehr, Marcos Nogueira Eberlin
Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Ciências Médicas
Made available in DSpace on 2018-08-26T10:40:41Z (GMT). No. of bitstreams: 1 SantosJunior_JulioCesar_M.pdf: 4092105 bytes, checksum: 8809a688f7411f1a87fd956c6674fe41 (MD5) Previous issue date: 2014
Resumo: Embora as anfetaminas estejam proibidas no Brasil, elas continuam sendo adquiridas ilegalmente assim como os canabinóides e cocaína, que representam um dos principais problemas de saúde pública a serem enfrentados no nosso país. Um dos grandes desafios desta área é a dificuldade de obtenção de material para exames periciais. O humor vítreo por encontrar-se isolado em um compartimento relativamente protegido de contaminação externa, invasão de microorganismos e traumatismos em geral, bem como por sua simplicidade/estabilidade analítica e esterilidade durante um longo período após a morte constitui-se como uma excelente amostra para a determinação de xenobióticos em corpos politraumatizados, carbonizados ou em decomposição, auxiliando na delegação da causa mortis. O uso da espectrometria de massas e o advento de novas metodologias de ionização são ferramentas essenciais à toxicologia forense, a V-EASI (venture easy ambient sonic-spray), é uma fonte de ionização de fácil aplicação e instalação, que não requer fluxo de eluente e os demais fatores utilizados nas fontes comerciais. Além disso, o uso da espectrometria de massas de ressonância ciclotrônica de íons por transformada de Fourier (FT-ICR-MS) de ultra-alta resolução e exatidão (valores de m/z exatos) leva a exata composição molecular, alcançando erros abaixo de 1 ppm (partes-por-milhão). Perante isso a avaliação da fórmula molecular normalmente é inequívoca. Quando acoplada a ionização por eletrospray (ESI) espécies moleculares suaves são formadas reduzindo a complexidade do espectro e produzindo informação composicional livre de fragmentos em misturas complexas facilitando sua compreensão. Portanto este trabalho visa o desenvolvimento de metodologias analíticas para análise de drogas de abuso presentes em humor vítreo, empregando o uso de técnicas modernas de espectrometria de massas (FT-ICR-MS e V-EASI-MS)
Abstract: Although amphetamines are banned in Brazil, they remain illegally acquired as cannabinoids and cocaine, which account for a public health task to be faced in this country. The major challenge is to obtain material for investigation exams. The vitreous humor constitutes a good alternative for these exams, since it occurs isolated in a protected space, free of external contamination and of microorganisms and traumatisms, and also due to its analytical stability and sterility preserving it for a long period after death. Moreover, the vitreous humor constitutes an excellent sample for the determination of xenobiotics even in polytraumatized bodies, carbonized or in decomposition, involved in the causa mortis. The use of mass spectrometry and the advent of new ionization methods are essential tools for forensic toxicology, the V-EASI (venture easy ambient sonic-spray), is a source of ionization easy to use and install, not requiring nitrogen flow, eluent flow and other factors used in commercial sources. Furthermore, the use of Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) provides ultra high resolution and accuracy in mass analysis and its accurate m/z values lead to the exact molecular composition, reaching errors below 1 ppm (parts-per-million) on normal operational conditions, the assigned molecular formula are normally unequivocal. When electrospray ionization (ESI) is used, soft molecular species are formed reducing spectra complexity and providing fragment-free compositional information about complex mixtures facilitating comprehension. Therefore, this work aims at the development of analytical methodologies for the analysis of drugs of abuse present in the vitreous humor, employing the use of modern techniques of mass spectrometry (FT-ICR-MS and V-EASI-MS
Mestrado
Ciencias Biomedicas
Mestre em Ciências Médicas

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34

Jackson, P. J. "Investigations of supercritical fluid chromatography, supercritical fluid extraction and capillary electrophoresis combined with mass spectrometry for the analysis of drugs of forensic interest." Thesis, Swansea University, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.637384.

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The major objective of these investigations was to develop a total assay for quantifying drugs of forensic interest in biological fluids that have presented problems with more conventional procedures. Supercritical fluid techniques in combination with mass spectrometry provided the main basis of the studies reported in this thesis. The practical aspects of the combination of supercritical fluid techniques with mass spectrometry was also investigated with a view to increasing sensitivity and specificity. Chapter 1 provides an overview of basic chromatographic techniques such as gas chromatography (GC) and high performance liquid chromatography (HPLC). The development of supercritical fluid chromatgraphy (SFC) and capillary zone electrophoresis (CZE) were discussed in greater depth. A method was developed for the separation of a number of beta-blockers using CZE. The basic theory of mass spectrometry was also reviewed together with an example of electrospray ionization of some small polar pharmaceutical compounds. The development of interfaces capable of coupling SFC systems to a mass spectrometer was also reviewed. Chapter 2 gives an overview of the beta-blockers which were used as test compounds during method development. Supercritical fluid separations of the beta-blockers using UV and mass spectrometric detection were compared. SFC/MS using the thermospray interface proved to be the most sensitive. The use of a triple quadrupole mass spectrometer was utilised to provide an increase in specificity needed when detecting trace amounts of drug in complex matrices. Chapter 3 gave an overview of some of the common problems with conventional sample preparation techniques and how supercritical fluid extraction (SFE) may be used to overcome them. On-line SFE/SFC/MS was developed for analysis of beta-blockers in horse and human blood fluids with quantitative results obtained from off-line SFE/HPLC/MS. Chapter 4 describes the use of double charge transfer (DCT) spectroscopy to gain information on ground and excited electronic states of doubly charged ions. The final chapter describes the instrumentation and experimental conditions used in these investigations.

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Nyadong, Leonard. "Ambient ionization mass spectrometry for the forensic screening of pharmaceuticals and the determination of potential drug candidates." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31694.

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Thesis (Ph.D)--Chemistry and Biochemistry, Georgia Institute of Technology, 2010.
Committee Chair: FernÃ¡ndez, Facundo; Committee Member: Bottomley, Lawrence; Committee Member: Mizaikoff, Boris; Committee Member: Orlando, Thomas; Committee Member: Prausnitz, Mark. Part of the SMARTech Electronic Thesis and Dissertation Collection.

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Lai, Hanh Tuyet. "The Construction and Optimization on an Ion Mobility Spectrometer for the Analysis of Explosives and Drugs." FIU Digital Commons, 2010. http://digitalcommons.fiu.edu/etd/169.

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Today, over 15,000 Ion Mobility Spectrometry (IMS) analyzers are employed at worldwide security checkpoints to detect explosives and illicit drugs. Current portal IMS instruments and other electronic nose technologies detect explosives and drugs by analyzing samples containing the headspace air and loose particles residing on a surface. Canines can outperform these systems at sampling and detecting the low vapor pressure explosives and drugs, such as RDX, PETN, cocaine, and MDMA, because these biological detectors target the volatile signature compounds available in the headspace rather than the non-volatile parent compounds of explosives and drugs. In this dissertation research volatile signature compounds available in the headspace over explosive and drug samples were detected using SPME as a headspace sampling tool coupled to an IMS analyzer. A Genetic Algorithm (GA) technique was developed to optimize the operating conditions of a commercial IMS (GE Itemizer 2), leading to the successful detection of plastic explosives (Detasheet, Semtex H, and C-4) and illicit drugs (cocaine, MDMA, and marijuana). Short sampling times (between 10 sec to 5 min) were adequate to extract and preconcentrate sufficient analytes (> 20 ng) representing the volatile signatures in the headspace of a 15 mL glass vial or a quart-sized can containing ≤ 1 g of the bulk explosive or drug. Furthermore, a research grade IMS with flexibility for changing operating conditions and physical configurations was designed and fabricated to accommodate future research into different analytes or physical configurations. The design and construction of the FIU-IMS were facilitated by computer modeling and simulation of ion’s behavior within an IMS. The simulation method developed uses SIMION/SDS and was evaluated with experimental data collected using a commercial IMS (PCP Phemto Chem 110). The FIU-IMS instrument has comparable performance to the GE Itemizer 2 (average resolving power of 14, resolution of 3 between two drugs and two explosives, and LODs range from 0.7 to 9 ng). The results from this dissertation further advance the concept of targeting volatile components to presumptively detect the presence of concealed bulk explosives and drugs by SPME-IMS, and the new FIU-IMS provides a flexible platform for future IMS research projects.

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Williams, Kristina Charlene. "Direct Inject Mass Spectrometry for Illicit Chemistry Detection and Characterization." Thesis, University of North Texas, 2016. https://digital.library.unt.edu/ark:/67531/metadc849747/.

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The field of direct inject mass spectrometry includes a massive host of ambient ionization techniques that are especially useful for forensic analysts. Whether the sample is trace amounts of drugs or explosives or bulk amounts of synthetic drugs from a clandestine laboratory, the analysis of forensic evidence requires minimal sample preparation, evidence preservation, and high sensitivity. Direct inject mass spectrometry techniques can rarely provide all of these. Direct analyte-probed nanoextraction coupled to nanospray ionization mass spectrometry, however, is certainly capable of achieving these goals. As a multifaceted tool developed in the Verbeck laboratory, many forensic applications have since been investigated (trace drug and explosives analysis). Direct inject mass spectrometry can also be easily coupled to assays to obtain additional information about the analytes in question. By performing a parallel artificial membrane assay or a cell membrane stationary phase extraction prior to direct infusion of the sample, membrane permeability data and receptor activity data can be obtained in addition to the mass spectral data that was already being collected. This is particularly useful for characterizing illicit drugs and their analogues for a biologically relevant way to schedule new psychoactive substances.

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Pereira, Denize Duarte. "Determinação de Flunitrazepam e 7¬aminoflunitrazepam em soro por cromatografia líquida de alta eficiência acoplada à espectrometria de massa em tandem com a utilização de extração on line: aspecto forense." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-29012018-154046/.

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Atualmente os benzodiazepínicos constituem o grupo de fármacos de prescrição mais consumidas em todo o mundo. Além da utilização desta classe farmacológica como fármacos de abuso, mais recentemente seu uso está associado a uma nova cultura psicodélica emergente. O termo \"club drugs\" tem sido usado para descrever estes fármacos que levam a efeitos psicodélicos e euforizantes. Acresça-se a isto à preocupante utilização destas substâncias em situações de estupro e/ou assalto, as chamadas \"drug-facilitated sexual assault\", destacando-se o flunitrazepam. Devido às pequenas doses administradas e a extensiva metabolização, a identificação do flunitrazepam e seus metabólitos torna-se dificultada em relação a outros benzodiazepínicos. O presente trabalho constitui validação de metodologia analítica que permita a correta identificação e quantificação de flunitrazepam e seu principal produto de biotransformação, o 7-aminoflunitrazepam, em soro. O método desenvolvido mostrou boa linearidade, precisão, exatidão, rendimento e capacidade de detectar os analitos mesmo em baixas concentrações, permitindo desta forma a inferência sobre a realidade dos casos onde se utiliza este fármaco sem fins terapêuticos.
Currently the benzodiazepines are one of the most consumed groups among the prescripton drugs in the world. Beside this, they have been used as drugs of abuse and more recently their use is associated with the new emerging psychodelic culture. The term \"club drugs\" has been used to describe these drugs that cause psychodelic and euphoric effects. In addition to this, there is a growing concern with the use of these substances related to \"drug-facilitated sexual assault\", among of which Flunitrazepan is pointed out as one of the most important . Due to the small doses involved in the consumption for this purpose and also the extense biotransformation, the identification of this analyte and its metabolites become more difficult than that of other benzodiazeines. This study provides an analytical validation method that enables correct identification and quantification of Flunitrazepam and its main biotransformation product, the 7-aminoflunitrazepam, in serum. The method developed demonstrates good linearity, precision, accuracy, recovery and capacity of detect the analytes, even in low concentration. Thus making possible to makes inferences regarding the reality of cases where it is used as a drug without therapeutic use.

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Tjäderborn, Micaela. "Psychoactive prescription drug use disorders, misuse and abuse : Pharmacoepidemiological aspects." Doctoral thesis, Linköpings universitet, Avdelningen för läkemedelsforskning, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-130768.

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Background: There is a widespread and increasing use of psychoactive prescription drugs, such as opioid analgesics, anxiolytics, hypnotics and anti-epileptics, but their use is associated with a risk of drug use disorder, misuse and abuse. Today, these are globally recognized and emerging public health concerns. Aim: The aim of this thesis is to estimate the prevalence of psychoactive prescription drug (PPD) use disorders, misuse and abuse, and to investigate the association with some potential risk factors. Methods: A study using register data from forensic cause of death investigations investigated and described cases of fatal unintentional intoxication with tramadol (Study I). Based on register data on spontaneously reported adverse drug reactions (ADRs) reported cases of tramadol dependence were investigated and summarised (Study II). In a study in suspected drug-impaired drivers with a toxicology analysis confirming the intake of one out of five pre-specified PPDs, the prevalence of non-prescribed use was assessed and associated factors were investigated (Study III). From a cohort of patients initiating prescribed treatment with pregabalin, using data on prescription fills, a study investigated longitudinal utilisation patterns during five years with regards to use of the drug above the maximum approved daily dose (MAD), and factors associated with the utilisation patterns (Study IV). Results: In the first study, 17 cases of unintentional intoxications were identified, of which more concerned men, the median age was 44 years and the majority used multiple psychoactive substances (alcohol, illicit drugs and prescription drugs). The second study identified 104 spontaneously reported cases of tramadol dependence, in which more concerned women, the median age was 45 years, and a third reported a history of substance abuse and 40% of past psychoactive medication use. In the third study, more than half of the individuals suspected of drug-impaired driving used the drug without a recent prescription. Non prescribed use was most frequent in users of benzodiazepines and tramadol, and was more likely in younger individuals and in multiple-substance users. In the last paper five longitudinal utilisation patterns were found in pregabalin users, with two patterns associated with a particularly high risk of doses above the maximum approved dosing recommendation. This pattern of use was associated with male sex, younger age, non-urban residency and a recent prescribed treatment with an antiepileptic or opioid analgesic drug. Conclusions: This thesis shows that psychoactive prescription drug use disorders, misuse and abuse occur and may have serious and even fatal consequences. The prevalence varies between different drugs and populations. Abuse and misuse seem to be more common in young people. Fatal intoxications and misuse of prescribed drugs may be more common in men, while drug use disorders following prescribed treatment may be more common in women and non-prescribed use equally distributed between women and men. Individuals with a history of mental illness, substance use disorder or abuse, or of past use of psychoactive medications are likely important risk groups. In summary, the findings suggest a potential for improvements in the utilisation of psychoactive prescription drugs. The results may be useful in the planning of clinical and regulatory preventive interventions to promote the rational, individualised and safe use of such drugs.

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Rust, Kristina Yasmin Verfasser], and Hans H. [Akademischer Betreuer] [Maurer. "Identification and validated quantification of drugs of abuse, medicaments and their metabolites in blood and hair using liquid chromatographic : tandem mass spectrometric techniques in forensic toxicology and therapeutic drug monitoring / Kristina Yasmin Rust. Betreuer: Hans H. Maurer." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2012. http://d-nb.info/1052551173/34.

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Costa, José Luiz da. "Eletroforese capilar como ferramenta analítica para toxicologia forense." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-23092008-104730/.

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No primeiro capítulo deste trabalho, são apresentados aspectos gerais sobre toxicologia forense e sobre a eletroforese capilar, onde se buscou mostrar como a técnica analítica pode ser útil para aplicações forenses. O segundo capítulo apresenta o desenvolvimento de metodologia analítica baseada em eletroforese capilar com detecção por arranjo de diodos para determinação de drogas de abuso ou seus produtos de biotransformação em humor vítreo. Foram estudados parâmetros como a composição do eletrólito de corrida (com especial atenção ao fenômeno de eletrodispersão), pré-concentração online (stacking) e modo de extração dos analitos. Foi obtida completa separação eletroforética de 12 analitos investigados em menos de 10 minutos de corrida. Os parâmetros de confiança analítica do método mostraram este é perfeitamente aplicável às análises toxicológicas com finalidade forense. O terceiro capítulo apresenta a elaboração de metodologia analítica baseada em eletroforese capilar acoplada a espectrometria de massas para determinação de cocaína e cinco produtos de biotransformação em urina, com procedimento de preparo da amostra biológica simplificado. O procedimento desenvolvido apresentou sensibilidade adequada para verificação de intoxicações agudas por cocaína, e a espectrometria de massas acrescentou grande seletividade à análise, principalmente quando a detecção foi realizada pela seleção do íon-pai e fragmentos gerados a 34% de energia de colisão. O terceiro capítulo apresenta o desenvolvimento de método simples e rápido para determinação de MDMA em comprimidos de Ecstasy usando eletroforese capilar de zona. Na corrida eletroforética desenvolvida, é possível determinar a concentração de MDMA em menos de dois minutos (usando procaína com padrão interno). O método desenvolvido foi comparado ao utilizado rotineiramente no Núcleo de Análise Instrumental do Instituto de Criminalística de São Paulo, baseado em cromatografia líquida de alta eficiência com detecção por fluorescência. O método eletroforético desenvolvido foi cinco vezes mais rápido do que o método de referência, permitindo maior produtividade sem que houvesse perda da qualidade do resultado. Por fim, o capítulo 4 apresenta as considerações finais deste trabalho, onde se pode concluir que a eletroforese capilar, ainda que pouco utilizada em laboratórios forenses brasileiros, pode ser ferramenta de grande utilidade nas análises toxicológicas destinadas a esta finalidade.
In the first chapter of this thesis, general aspects on forensic toxicology and capillary electrophoresis are presented, aiming to show how the analytical technique can be useful for forensic applications. The second chapter presents the development of analytical methodology based on capillary electrophoresis with diode array detection for determining drugs of abuse and/or their biotransformation products in vitreous humor. Parameters such as the composition of background electrolyte (with special attention to the phenomenon of electrodispersion), online pre-concentration (stacking) and sample preparation procedures were objects of study. The complete electrophoretic separation of 12 investigated analytes was obtained within 10 minutes of run. The validation parameters of the method have shown that this is perfectly applicable to toxicological analyses with forensic purposes. The third chapter presents the elaboration of analytical methodology based on capillary electrophoresis coupled to mass spectrometry for determining cocaine and five biotransformation products in urine, with simple sample preparation. The process developed presented adequate sensitivity for the verification of acute intoxications by cocaine, and mass spectrometry contributed with great selectiveness to the analysis, mainly when the detection was conducted by the selection of the molecular-ion and fragments generated at 34% of collision energy. The fourth chapter presents the development of a simple and quick method for determining MDMA in tablets of Ecstasy using capillary zone electrophoresis. In the running condition, it is possible to determine the concentration of MDMA in less than two minutes (using procaine with internal standard). The method developed was compared with the one routinely used at Núcleo de Análise Instrumental do Instituto de Criminalística de São Paulo, based on high performance liquid chromatography with fluorescence detection. The electrophoretic method developed was five times faster than the reference one, allowing higher productivity without loss of quality in the result. Finally, chapter five presents the final considerations of this thesis, where it is possible to conclude that capillary electrophoresis, even being little utilized in Brazilian forensic laboratories, can be a tool of great utility in toxicological analyses destined to this purpose.

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Ochoa, Mariela L. "Forensic and Proteomic Applications of Thermal Desorption Ion Mobility Spectrometry and Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry." Ohio University / OhioLINK, 2005. http://www.ohiolink.edu/etd/view.cgi?ohiou1113585811.

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Herrin, Amy Elizabeth. "Assessing, Modifying, and Combining Data Fields from the Virginia Office of the Chief Medical Examiner (OCME) Dataset and the Virginia Department of Forensic Science (DFS) Datasets in Order to Compare Concentrations of Selected Drugs." VCU Scholars Compass, 2006. http://scholarscompass.vcu.edu/etd/1057.

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The Medical Examiner of Virginia (ME) dataset and the Virginia Department of Forensic Science Driving Under the Influence of Drugs (DUI) datasets were used to determine whether people have the potential to develop tolerances to diphenhydramine, cocaine, oxycodone, hydrocodone, methadone, and morphine. These datasets included the years 2000-2004 and were used to compare the concentrations of these six drugs between people who died from a drug-related cause of death (of the drug of interest) and people who were pulled over for driving under the influence. Three drug pattern groups were created to divide each of the six drug-specific datasets in order to compare concentrations between individuals with the drug alone, the drug and ethanol, or a poly pharmacy of drugs (multiple drugs). An ANOVA model was used to determine if there was an interaction effect between the source dataset (ME or DUI) and the drug pattern groups. For diphenhydramine and cocaine, an interaction was statistically significant, but for the other drugs, it was not significant. The other four drug-specific datasets showed that the DUI and ME were statistically significantly different from each other, and all of those datasets except for methadone showed that there was a statistically significant difference between at least two drug pattern groups. Showing that all of these datasets showed differences between the ME and DUI datasets did not provide sufficient evidence to suggest the development of tolerances to each of the six drugs. One exception was with methadone because there were 14 individuals that had what is defined as a "clinical 'lethal' blood concentration". These individuals provide some evidence for the possibility of developing tolerances.The main outcomes of this study include suggesting changes to make to the ME datasets and the DUI datasets with regard to the way data is kept and collected. Several problems with the fields of these datasets arose before beginning the analysis and had to be corrected. Some of the changes suggested are currently being considered at the Virginia Office of the Chief Medical Examiner as they are beginning to restructure their database.

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Macias, Michael S. "The Development of an Optimized System of Narcotic and Explosive Contraband Mimics for Calibration and Training of Biological Detectors." FIU Digital Commons, 2009. http://digitalcommons.fiu.edu/etd/123.

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Current commercially available mimics contain varying amounts of either the actual explosive/drug or the chemical compound of suspected interest by biological detectors. As a result, there is significant interest in determining the dominant chemical odor signatures of the mimics, often referred to as pseudos, particularly when compared to the genuine contraband material. This dissertation discusses results obtained from the analysis of drug and explosive headspace related to the odor profiles as recognized by trained detection canines. Analysis was performed through the use of headspace solid phase microextraction in conjunction with gas chromatography mass spectrometry (HS-SPME-GC-MS). Upon determination of specific odors, field trials were held using a combination of the target odors with COMPS. Piperonal was shown to be a dominant odor compound in the headspace of some ecstasy samples and a recognizable odor mimic by trained detection canines. It was also shown that detection canines could be imprinted on piperonal COMPS and correctly identify ecstasy samples at a threshold level of approximately 100ng/s. Isosafrole and/or MDP-2-POH show potential as training aid mimics for non-piperonal based MDMA. Acetic acid was shown to be dominant in the headspace of heroin samples and verified as a dominant odor in commercial vinegar samples; however, no common, secondary compound was detected in the headspace of either. Because of the similarities detected within respective explosive classes, several compounds were chosen for explosive mimics. A single based smokeless powder with a detectable level of 2,4-dinitrotoluene, a double based smokeless powder with a detectable level of nitroglycerine, 2-ethyl-1-hexanol, DMNB, ethyl centralite and diphenylamine were shown to be accurate mimics for TNT-based explosives, NG-based explosives, plastic explosives, tagged explosives, and smokeless powders, respectively. The combination of these six odors represents a comprehensive explosive odor kit with positive results for imprint on detection canines. As a proof of concept, the chemical compound PFTBA showed promise as a possible universal, non-target odor compound for comparison and calibration of detection canines and instrumentation. In a comparison study of shape versus vibration odor theory, the detection of d-methyl benzoate and methyl benzoate was explored using canine detectors. While results did not overwhelmingly substantiate either theory, shape odor theory provides a better explanation of the canine and human subject responses.

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Costa, José Luiz da. "Determinação de 3,4-metilenodioximetanfetamina (MDMA - Ecstasy), 3,4-metilenodioxietilanfetamina (MDEA - Eve) e 3,4-metilenodioxianfetamina (MDA) em fluidos biológicos por cromatografia líquida de alta eficiência: aspecto forense." Universidade de São Paulo, 2004. http://www.teses.usp.br/teses/disponiveis/9/9141/tde-11032005-190039/.

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Em todo o mundo é crescente o uso drogas de abuso sintéticas conhecidas com designer drugs. Os principais representantes desta classe são o Ecstasy ou 3,4-metilenodioximetanfetamina (MDMA) e o Eve ou 3,4-metilenodioxietilanfetamina (MDEA), substâncias com efeitos estimulantes e alucinógenos. No Brasil é crescente sua divulgação pela mídia e o uso recreacional tem sido constatado em vários pacientes que buscam tratamento nas clínicas para dependentes. O presente trabalho constitui validação de metodologia analítica para o diagnóstico laboratorial do uso de MDMA, MDEA e seu produto de biotransformação, o 3,4-metilenodioxianfetamina (MDA), em sangue total e urina, por cromatografia líquida de alta eficiência com detecção por fluorescência. Os métodos desenvolvidos mostraram boa linearidade, precisão, exatidão, rendimento e capacidade de detectar os analitos mesmos quando presentes em baixas concentrações, o que permite sua aplicação na verificação da intoxicação aguda quanto no uso recreacional destas drogas de abuso.
There is a worldwide increase in the use of the synthetic drugs of abuse known as designer drugs. The main representatives of this class are Ecstasy or 3,4-methylenodioxymethamphetamine (MDMA) and Eve or 3,4- methylenodioxyethylamphetamine (MDEA), substances with stimulant and hallucinogenic effects. In Brazil media coverage of them is on the increase and their recreational is in evidence by the growing numbers of patients who seek treatment at drug treatment centers. This paper validates the analytical methodology for the laboratory diagnosis of the use of MDMA, MDEA and their product of biotransformation, 3,4-methylenodioxyamphetamine (MDA), in whole blood and urine by high performance liquid chromatography with fluorescence. The developed methods showed good linearity, precision, accuracy, yield and capacity to detect analytes even when present in low concentrations, which enables its application in cases high intoxication as well as in cases of the recreational use of these drugs of abuse.

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SHIBUYA, ELISA K. "Rastreamento da origem geográfica de amostras de maconha apreendidas nas ruas de São Paulo, por meio de assinaturas químicas." reponame:Repositório Institucional do IPEN, 2005. http://repositorio.ipen.br:8080/xmlui/handle/123456789/11279.

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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
Tese (Doutoramento)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
FAPESP:00/09814-0

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Araujo, William Reis de. "Desenvolvimento de sensores eletroquímicos e colorimétricos para aplicações em amostras de interesse forense." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/46/46136/tde-18082016-084906/.

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Esta tese apresenta os estudos e esforços visando ao desenvolvimento de sensores químicos para aplicações diversas na área forense. Foram desenvolvidos métodos eletroanalíticos para detecção e quantificação de alguns compostos comumente encontrados na adulteração de amostras de drogas de abuso (procaína, fenacetina, aminopirina, paracetamol, levamisol), além da cocaína e estudos fundamentais sobre o comportamento eletroquímico desses compostos. Empregaram-se também métodos eletroquímicos para quantificação de compostos tóxicos e perigosos como explosivos (ácido pícrico) e melamina por exemplo. Os trabalhos utilizando sensores eletroquímicos contemplam modificações eletroquímicas das superfícies eletródicas, utilização de sensores com polímeros molecularmentes impressos (MIP) e eletrodos descartáveis em papel utilizando diferentes técnicas voltamétricas e amperométricas, eletrodo disco rotatório (EDR) e microbalança de cristal de quartzo. Além da fabricação de dispositivos analíticos descartáveis em papel empregando detecção eletroquímica utilizou-se também a detecção colorimétrica para quantificação de alguns dos principais adulterantes de amostras de apreensão de cocaína, como procaína e fenacetina, bem como análises e discriminações de compostos explosivos (peroxi e nitro compostos) nessas plataformas portáteis e de baixo custo. Os métodos foram sempre desenvolvidos visando característicos como: facilidade, praticidade, baixo custo e portabilidade para análises diretamente no local de medida com mínima infraestrutura laboratorial. Por fim, são apresentados alguns estudos realizados durante estágio de pesquisa no exterior (Universidade da Califórnia - San Diego (UCSD)) na área de Wearable Sensors, em que foram desenvolvidos métodos para análises de micronutrientes no suor (zinco) e um metabólito (ácido úrico) na saliva usando sensores aplicados diretamente no corpo humano.
This thesis shows studies and efforts to the development of chemical sensors for different applications in the forensic field. Electroanalytical methods were developed for detection and quantification of some compounds (procaine, phenacetin, aminopyrine, acetaminophen, levamisole) commonly found in the drug of abuse adulteration process and cocaine, as well as, fundamental studies about the electrochemical behavior of these compounds. It was also employed electrochemical methods for quantification of hazardous compounds such as explosives (picric acid) and melamine. Analytical methods with electrochemical sensors included electrochemical modification of electrodic surfaces, molecularly imprinted polymers (MIP), and paper disposable electrochemical devices using different voltammetric and amperometric techniques, rotating disc electrode (RDE) and quartz crystal microbalance. In addition to the fabrication of paper disposable analytical devices with electrochemical detection, it was also used the colorimetric detection to quantify some of the major adulterants in cocaine seizure samples, such as procaine and phenacetin, as well as analysis and discrimination of explosive compounds (peroxy and nitro explosives) in these low cost portable platforms. All proposed methods were always developed aming at theses characteristics: ease, convenience, low cost and portability for analysis directly at the measurement site with minimal laboratory infrastructure. Finally, we presented some studies conducted during research internship abroad (University of California - San Diego (UCSD)) in the area of Wearable Sensors, which have been developed methods for micronutrient analysis in sweat (Zn) and a metabolite (Uric Acid) in saliva using sensors applied directly to the human body

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Pipes, Latisha C. "Detection of Illicit Drug Use in Blood: A Validation Study of Solid Phase Extraction Coupled with Liquid Chromatography and Tandem Mass Spectrometry." Bowling Green State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1587613608312474.

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Carvalho, Thays Colletes de. "Espectrometria de massas por paper spray Ionization: técnica analítica versátil para os desafios da química forense." Universidade Federal de Goiás, 2018. http://repositorio.bc.ufg.br/tede/handle/tede/9094.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Ionization is a crucial step in mass spectrometry (MS) and governs the versatility of this important analytical technique. Ionization is responsible for transferring atoms and molecules, in their respective ionized forms, into the high vacuum environment of mass spectrometers, where they are discriminated as a function of their m/z ratio. Among the several techniques of ionization of MS, the technique of ionization by Paper spray (PS) is one of the simplest, versatile and can be implemented easily in MS system. In this work, several PS-MS applications in the forensic area were developed, demonstrating their ability to screen new synthetic drugs as a complementary tool to the thin layer chromatography (TLC) method and as a tool to monitor Date-rape Drugs in blood. In the first application, PS-MS was shown to be an effective and rapid method for the identification of synthetic drugs lysergic acid diethylamide (LSD), 2,5-dimethoxy-4-chloroamphetamine (DOC), 2,5-dimethoxy-4-bromoamphetamine (DOB), 25C-NBOMe, 25B-NBOMe and 25I-NBOMe) in bottles, both by the isotopic profile of the substances and by the fragmentation presented in tandem mass spectrometry. In the second application, the TLC was coupled to the PS-MS in order to achieve greater reliability in the CCD results. In this way, a CCD method for the analysis of cocaine and adulterants (caffeine, benzocaine, lidocaine and phenacetin) was optimized by evaluating its sensitivity and selectivity. In order to improve the Detection and Quantification Limits for cocaine and adulterants, the spots were analyzed by PS-MS, obtaining improvements in the. Finally, in order to solve the low PS-MS selectivity, a new substrate was developed, especially when the analytical target is in complex mixtures, such as blood. It is a membrane coated with a molecularly printed polymer (MIP) with dual function: simultaneous extraction and ionization of targets in the same device. The developed membrane was applied in the determination of benzodiazepines in blood samples from alleged date rape- drugs victims. Blood is a complex sample containing several compounds that can suppress the analyte signal. With this modification, any suppression is avoided, obtaining excellent results, both qualitative and quantitative. In conclusion, PS-MS is a fast and low-cost technique that can replace or complement conventional analyzes in a laboratory of expertise, increasing the productivity of Brazilian justice.
A ionização é uma etapa crucial em espectrometria de massas (MS) e rege a versatilidade desta importante técnica analítica. A ionização é a responsável por transferir átomos e moléculas, em suas respectivas formas ionizadas, para o ambiente de alto vácuo dos espectrômetros de massas, onde são discriminados em função de sua razão massa sobre carga (m/z). Dentre as diversas técnicas de ionização de MS, a técnica de ionização por Paper spray (PS) é uma das mais simples, versátil e pode ser implementada facilmente em sistema de MS. Nesse trabalho diversas aplicações do PS-MS na área forense foram desenvolvidas, demonstrando sua capacidade para screening de novas drogas sintéticas, como ferramenta complementar ao método de cromatografia de camada delgada (TLC) e como ferramenta para monitorar “boa noite cinderela” em sangue. Na primeira aplicação, o PS-MS mostrou ser um método eficaz e rápido para identificação de drogas sintéticas dietilamida do ácido lisérgico (LSD), 2,5-dimetoxi-4-cloroanfetamina (DOC), 2,5-dimetoxi-4- bromoanfetamina (DOB), 25C-NBOMe, 25B- NBOMe e 25I-NBOMe) em selos, tanto pelo perfil isotópico das substâncias, quanto pela fragmentação apresentada na espectrometria de massas tandem. Já na segunda aplicação, acoplou-se TLC ao PS-MS visando alcançar maior confiabilidade nos resultados de TLC. Desta maneira, otimizou-se um método de TLC para análise de cocaína e adulterantes (cafeína, benzocaína, lidocaína e fenacetina) avaliando sua sensibilidade e seletividade. Com intuito de melhorar os Limites de Detecção e Quantificação para a cocaína e adulterantes, os spots foram analisados por PS-MS, obtendo melhorias nos resultados. Por fim, com o intuito de resolver a baixa seletividade do PS-MS, um novo substrato foi desenvolvido, principalmente quando o alvo analítico está em misturas complexas, como sangue. Trata-se de uma membrana recoberta com um polímero molecularmente impresso (MIP) com dupla função: extração e ionização simultânea de alvos em um mesmo dispositivo. A membrana desenvolvida foi aplicada na determinação de benzodiazepínicos em amostras de sangue de supostas vítimas de benzodiazepínicos. O sangue é uma amostra complexa que contém vários compostos que podem suprimir o sinal do analito. Com essa modificação qualquer supressão é evitada, conseguindo-se ótimos resultados, tanto qualitativos quanto quantitativos. Sendo assim, o PS-MS é uma técnica rápida e de baixo custo, que pode substituir ou complementar as análises convencionais em um laboratório de perícia, aumentando a produtividade da justiça brasileira.

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Paul, Richard. "New developments in analytical toxicology for the investigation of drug facilitated crime." Thesis, University of South Wales, 2007. https://pure.southwales.ac.uk/en/studentthesis/new-developments-in-analytical-toxicology-for-the-investigation-of-drug-facilitated-crime(c2b2b4e3-b8c5-471f-bf3b-daca545d4afa).html.

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Drug facilitated assault (DFA) is an increasing problem in the UK. The crime often occurs through the surreptitious administration of a drug into a victims drink, rendering the victim unable to resist the assault. The detection of these drugs in a biological specimen from the victim is one of the most challenging facets of forensic chemistry. Drug concentrations can be very low, as often only a single dose is administered, and the pharmacodynamics of commonly employed drugs further hinders the testing process. The research presented in this work shows the development of several new assays for the detection of flunitrazepam, gamma-hydroxybutyrate (GHB) and ethyl glucuronide (EtG) in a variety of biological matrices. New methods of drug testing in blood and urine are demonstrated, as well as interesting developments in the field of hair testing. Using hair to detect drug exposure allows a much wider window of detection than the more traditional matrices of blood and urine. New methods are presented in this work using gas chromatography-tandem mass spectrometry (GCMS/MS) to detect drugs in hair. Validation data is presented along with the results of authentic DFA testing. All aspects of the drug testing procedure have been evaluated, from new extraction techniques utilising water instead of solvents, to novel clean up stages involving the unique combination of SFE and SPME. Several confirmation techniques are explored including single quadrupole, triple quadrupole and ion trap mass spectrometry. In addition to developing assays for DFA cases, the versatility of this type of analytical chemistry is explored in two population studies. The first study evaluates alcohol consumption between two groups; drugs users and non drug users in medico-legal cases. There is an anecdotal belief amongst drug clinic staff that alcohol use is lower in drugs users than it is in non drug users. This study presents the first scientific confirmation of this belief through EtG (an alcohol metabolite) testing in hair of the two groups. The second study investigates whether there is a correlation between EtG and cocaethylene (a metabolite of cocaine only produced in the presence of alcohol) in cocaine users. Results f this study suggest that there is no positive correlation between the two compounds. The research presented in this thesis aims to further the analytical science surrounding FA investigation and provide accurate, sensitive and reliable methodology for drug esting in blood, urine and hair.

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Dissertations / Theses on the topic 'Forensic Drugs'

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