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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

It Permeated Everything: A Lived Experience of Slow Violence and Toxicological Disaster

Holmberg, Tara Jo 19 December 2022 (has links)
No description available.
102

Avaliação da presença de cocaína e anfetamina em amostras de sangue post mortem e de indivíduos vivos, utilizando técnica de microextração em fase líquida (HF-LPME) / Amphetamine, cocaine and tetrahydrocannabinol evaluation in blood samples of living people and post mortem blood samples using microextraction technique in liquid phase (HF-LPME).

Sanchez, Clovis 18 April 2018 (has links)
Estima-se atualmente que mais de 5% da população mundial vem fazendo uso recreativo de algum tipo de substância psicoativa, sendo que o direito a esse uso é tema recorrente da sociedade contemporânea. Por apresentar riscos associados à saúde e a segurança das populações, o uso abusivo dessas substâncias tem instigado a toxicologia social na busca de respostas, com as quais se possa caracterizar, analisar e gerenciar esses riscos. Drogas de grande consumo no Brasil são a anfetamina, cocaína e Cannabis sativa. Esta tese desenvolveu uma nova metodologia para detectar e quantificar anfetamina, cocaína e tetrahidrocanabinol em sangue total, com uso de microextração em fase líquida via fibra de polipropileno (HF-LPME), seguida de cromatografia gasosa acoplada a espectrometria de massa (GC-MS). Trata-se de uma técnica que apresenta vantagens sobre as tradicionais, uma vez que demanda quantidades menores de solvente orgânico, diminuindo riscos e custos de processo. Também propôs um estudo com a aplicação dos métodos em 69 amostras de sangue de vivos e de post mortem, as quais foram obtidas por convênio com a superintendência da polícia técnica científica de São Paulo (SPTC/SP). Os métodos desenvolvidos foram validados de acordo com diretrizes internacionais de interesse forense. Como resultado da validação, os métodos desenvolvidos se mostraram precisos e exatos para anfetamina e cocaína. O limite de detecção da cocaína foi de 5 ng . mL-1 e o limite de quantificação de 10 ng . mL-1. Quanto a anfetamina, os limites de detecção e de quantificação foram de 5 ng . mL-1. A técnica de HF-LPME não foi aplicável ao tetraidrocanabinol (Δ9-THC). Como resultado da análise das amostras, 40% delas apresentaram resultados positivos para cocaína. Desses positivos, 35% foram oriundos das matrizes de sangue de vivos e 64% oriundos de sangue post mortem. Nenhuma delas apresentou resultado quantificável para anfetamina. / It is currently estimated that more than 5% of the world\'s population has been doing recreational use of some kind of psychoactive substances and the legal right to such use is a recurring theme debated by contemporary society. Due to the risks associated with populations health and safety, the abusive use of these substances has been instigating by social toxicology to search for answers to characterize, analyze and manage these risks. Drugs of great consumption in Brazil are, amphetamine cocaine and marijuana. This thesis proposes to develop a new methodology to detect and quantify psychoactive drugs in whole blood with the use of liquid phase microextraction by polypropylene fiber (HFLPME), followed by gas chromatography coupled to mass spectrometry (GC-MS). It is a technique that presents advantages compared with traditional ones, because of the smaller amounts demands of organic solvent, reducing risks and process costs. It also proposes a study with 69 blood samples taken from living persons and post mortem blood samples, which were obtained by agreement with the Superintendency of São Paulo Scientific Technical Police (SPTC / SP). The methods developed were validated according to international guidelines of forensic interest. As a result of the validation, the methods developed were precise and accurate for amphetamine and cocaine. The limit of cocaine detection was 5 ng . mL-1 and the limit of quantification was 10 ng . mL-1. As for amphetamine, the limits of detection and quantification were 5 ng . mL-1. The HF-LPME technique was not applicable to tetrahydrocannabinol (Δ9-THC). As a result of the sample analysis, 40% of them presented positive results for cocaine. Of these, 35% were from blood samples taken from living persons and 64% from the post mortem blood samples. None of the samples presented quantifiable results for amphetamine.
103

Über die Aussagesicherheit der Substanzidentifizierung mittels HPLC-DAD in der systematischen toxikologischen Analyse unter Verwendung einer selbsterstellten UV-Spektrenbibliothek mit 2.682 Einträgen

Herzler, Matthias 17 March 2003 (has links)
In der vorliegenden Arbeit wurde die Leistungsfähigkeit der Hochleistungsflüssigchromatographie mit Photodiodenarraydetektion (HPLC-DAD) im Rahmen der Systematischen Toxikologischen Analyse (STA) umfassend untersucht, ein besonderer Schwerpunkt lag dabei auf der Aussagesicherheit bei der Substanzidentifizierung. Die Grundlage für diese Untersuchungen bildete die Messung der UV-Spektren und relativen Retentionszeiten (RRT) von 2.682 toxikologisch relevanten Substanzen mit Hilfe moderner Diodenarraydetektoren und unter einheitlichen experimentellen Bedingungen (Eluent: Acetonitril/ Phosphatpuffer pH 2,3; Trennsäule: Lichrospher RP8ec). Die erhaltenen Daten wurden zusammen mit weiteren Substanzinformationen in einer Spektrenbibliothek zusammengefasst, die als Buch und CD-ROM auch der Öffentlichkeit zugänglich gemacht wurde. Bei der Entwicklung eines Konzeptes zur Methodenvalidierung für die STA erwiesen sich insbesondere die Kenngrößen Selektivität und Spezifität als von zentraler Bedeutung. Unter Verwendung eines Fensteransatzes für die RRT und des Similarity Index (SI) für den Spektrenvergleich wurden sämtliche möglichen Substanzpaare aus der Spektrenbibliothek miteinander auf ihre Unterscheidbarkeit hin verglichen, wobei verschiedene RRT-Fensterbreiten und SI-Schwellenwerte zugrundegelegt wurden. Aus den Ergebnissen wurden Selektivitätsparameter wie die Relative Identification Power (RIP), die Discriminating Power (DP) und die Mean List Length (MLL) berechnet. Mit einer RIP von 84,2 %, einer MLL von 1,25 und einer DP von 0,9999 wurden für die Substanzidentifikation anhand von RRT + UV-Spektrum im Literaturvergleich sehr gute Ergebnisse erhalten. Die hohe Grad an Spezifität der UV-Spektren für den Einsatz in der STA wurde einerseits durch Auszählung sämtlicher in der Spektrenbibliothek gefundener Chromophore/Absorptionssysteme belegt: 1.650 verschiedene Absorptionssysteme wurden gefunden, über 60 % der Verbindungen trugen ein in diesem Substanzbestand einzigartiges Absorptionssystem. Andererseits wurde die computergestützte Unterscheidbarkeit zwischen verschiedenen Gruppen jeweils strukturell ähnlicher Wirkstoffe anhand des UV-Spektrums untersucht. Hierfür wurden 487 Substanzen in ein hierarchisches System von Haupt- und Untergruppen eingeteilt, zwischen denen anschließend mit Hilfe der Schrittweisen Diskriminanzanalyse (SDA) unterschieden werden sollte. Die sehr guten Klassifizierungsergebnisse und die Auflösung auch feiner struktureller Unterschiede, oftmals abseits des eigentlichen Absorptionssystems, lassen es grundsätzlich möglich erscheinen, auch Substanzen für die STA zu erschließen, die nicht in der Spektrenbibliothek enthalten sind. Insgesamt erwies sich die HPLC-DAD als hochselektives und -spezifisches Messverfahren, das zu Recht eine der wichtigsten STA-Methoden darstellt. / In this thesis the capability of high-performance liquid chromatography with photodiode array detection in the context of Systematical Toxicological Analysis (STA) was extensively investigated with a special focus on the certainty of substance identification. As the foundation for these investigations, UV spectra and relative retention times (RRT) of 2,682 toxicologically relevant compounds were recorded under uniform experimental conditions (mobile phase: acetonitrile/ phosphate buffer pH 2.3; column: Lichrospher RP8ec) using up-to-date photodiode array detectors. Together with additional substance information these data were built into a spectra library also made available to the public in the form of a book and a CD-ROM. During the development of a concept for the validation of a STA method, selectivity and specificity were found to be of central importance. Using a window approach for the RRT and the Similarity Index (SI) for spectral comparison, all possible substance pairs within the spectra library were examined in terms of their respective distinguishability, based on different RRT windows and SI threshold values. From the results selectivity parameters such as the Relative Identification Power (RIP), the Discriminating Power (DP), and the Mean List Length (MLL) were calculated. As compared to the literature, with a RIP of 84.2 %, a MLL of 1.25, and a DP of 0,9999 excellent results were obtained for the substance identification based on the combination of RRT and UV spectrum. The high degree of specificty of UV spectra for use in the STA was demonstrated on the one hand by counting all different chromophores/ absorption systems found in the spectra library: 1,650 systems were found, more than 60 % of the substances bore absorption systems unique in the dataset. On the other hand the computer-based distinction between different groups of structurally similar compounds on the basis of the UV spectrum was investigated by dividing 487 substances into a hierarchical system of main and subgroups and trying to distinguish between these groups using stepwise discriminant analysis (SDA). The highly satisfying classification results together with the resolution of fine structural differences, often remote from the actual absorption system, make it seem possible to also render substances not included in the spectra library accessible for the STA. In conclusion HPLC-DAD proved to be highly selective and specific, rightfully regarded as one of the most important STA methods.
104

Avaliação da presença de cocaína e anfetamina em amostras de sangue post mortem e de indivíduos vivos, utilizando técnica de microextração em fase líquida (HF-LPME) / Amphetamine, cocaine and tetrahydrocannabinol evaluation in blood samples of living people and post mortem blood samples using microextraction technique in liquid phase (HF-LPME).

Clovis Sanchez 18 April 2018 (has links)
Estima-se atualmente que mais de 5% da população mundial vem fazendo uso recreativo de algum tipo de substância psicoativa, sendo que o direito a esse uso é tema recorrente da sociedade contemporânea. Por apresentar riscos associados à saúde e a segurança das populações, o uso abusivo dessas substâncias tem instigado a toxicologia social na busca de respostas, com as quais se possa caracterizar, analisar e gerenciar esses riscos. Drogas de grande consumo no Brasil são a anfetamina, cocaína e Cannabis sativa. Esta tese desenvolveu uma nova metodologia para detectar e quantificar anfetamina, cocaína e tetrahidrocanabinol em sangue total, com uso de microextração em fase líquida via fibra de polipropileno (HF-LPME), seguida de cromatografia gasosa acoplada a espectrometria de massa (GC-MS). Trata-se de uma técnica que apresenta vantagens sobre as tradicionais, uma vez que demanda quantidades menores de solvente orgânico, diminuindo riscos e custos de processo. Também propôs um estudo com a aplicação dos métodos em 69 amostras de sangue de vivos e de post mortem, as quais foram obtidas por convênio com a superintendência da polícia técnica científica de São Paulo (SPTC/SP). Os métodos desenvolvidos foram validados de acordo com diretrizes internacionais de interesse forense. Como resultado da validação, os métodos desenvolvidos se mostraram precisos e exatos para anfetamina e cocaína. O limite de detecção da cocaína foi de 5 ng . mL-1 e o limite de quantificação de 10 ng . mL-1. Quanto a anfetamina, os limites de detecção e de quantificação foram de 5 ng . mL-1. A técnica de HF-LPME não foi aplicável ao tetraidrocanabinol (Δ9-THC). Como resultado da análise das amostras, 40% delas apresentaram resultados positivos para cocaína. Desses positivos, 35% foram oriundos das matrizes de sangue de vivos e 64% oriundos de sangue post mortem. Nenhuma delas apresentou resultado quantificável para anfetamina. / It is currently estimated that more than 5% of the world\'s population has been doing recreational use of some kind of psychoactive substances and the legal right to such use is a recurring theme debated by contemporary society. Due to the risks associated with populations health and safety, the abusive use of these substances has been instigating by social toxicology to search for answers to characterize, analyze and manage these risks. Drugs of great consumption in Brazil are, amphetamine cocaine and marijuana. This thesis proposes to develop a new methodology to detect and quantify psychoactive drugs in whole blood with the use of liquid phase microextraction by polypropylene fiber (HFLPME), followed by gas chromatography coupled to mass spectrometry (GC-MS). It is a technique that presents advantages compared with traditional ones, because of the smaller amounts demands of organic solvent, reducing risks and process costs. It also proposes a study with 69 blood samples taken from living persons and post mortem blood samples, which were obtained by agreement with the Superintendency of São Paulo Scientific Technical Police (SPTC / SP). The methods developed were validated according to international guidelines of forensic interest. As a result of the validation, the methods developed were precise and accurate for amphetamine and cocaine. The limit of cocaine detection was 5 ng . mL-1 and the limit of quantification was 10 ng . mL-1. As for amphetamine, the limits of detection and quantification were 5 ng . mL-1. The HF-LPME technique was not applicable to tetrahydrocannabinol (Δ9-THC). As a result of the sample analysis, 40% of them presented positive results for cocaine. Of these, 35% were from blood samples taken from living persons and 64% from the post mortem blood samples. None of the samples presented quantifiable results for amphetamine.
105

Etude du cycle de vie du Ticagrelor par une approche combinée prédictive et caractérisation structurale / Ticagrelor life cycle study combining prediction and structural characterization

Sadou Yaye, Hassane 05 February 2018 (has links)
Les scandales sanitaires ayant émaillé le médicament ont mis la sécurité d’utilisation au cœur des préoccupations des acteurs de santé. Tout au long de son cycle de vie, le médicament est susceptible d’exposition à des conditions de stress pouvant conduire à sa dégradation et potentiellement, à la modification du rapport bénéfice/risque. Ce problème est d’autant plus marqué en milieu hospitalier où les médicaments en post – AMM sont manipulés pour des besoins spécifiques des patients. Quid de la maîtrise des modifications de leurs microenvironnements ? Etendre son espace de connaissances est admis comme étant le meilleur moyen pour circonscrire ces phénomènes. Dans le cadre de ce projet doctoral, une stratégie d’étude du cycle de vie des médicaments en post – AMM a été mise en place afin de renforcer leur sécurité d’utilisation. Compte tenu de la place prépondérante des formes solides dans l’arsenal thérapeutique, le ticagrelor, un récent antiagrégant plaquettaire (AAP) présenté sous forme de comprimés, a été choisi pour cette étude. La première étape a consisté à l’utilisation des conditions de stress pour évaluer sa stabilité intrinsèque et l’élucidation structurale des produits de dégradations grâce au couplage LC-HR-MSn donnant accès aux compositions élémentaires. Les voies de dégradation ont été proposées et la sécurité des produits a été évaluée grâce à l’approche in silico. Par ailleurs, compte tenu de l’utilisation des AAP en association, dans la seconde partie de ce travail, l’extension de l’espace de connaissances du ticagrelor a permis d’envisager une stratégie de préformulation avec l’aspirine à l’état solide en utilisant des techniques complémentaires comme la LC-HR-MSn, la DSC, la DRX ou l’ATG. La formation d’un simple eutectique a été observée avec le mélange des deux principes actifs. Nous avons démontré que la dégradation du ticagrelor est liée à la décomposition de l’aspirine, modulée par les conditions environnementales. Le modèle d’étude du ticagrelor ouvre clairement des perspectives sur la maîtrise de la sécurité en l’élargissant à d’autres médicaments et pourra contribuer à leur recyclage approprié. / Tragedies caused by the misuse of pharmaceuticals have put the drug safety at the core of the concerns of healthcare providers. Throughout its life cycle, a drug may be subjected to environmental stresses, which can lead to its degradation. Thorough understanding about the susceptibility of a drug to degrade is an essential step to avoid it. This problem is in particular relevant in a hospital setting, where commercial drugs are usually applied to specific cases without a clear understanding of its limitations. As part of this PhD project, a life cycle study strategy for a commercial drug has been implemented in order to increase its safety in use. Given the prominence of solid forms in the therapeutic arsenal, ticagrelor, a recent antiplatelet agent (APA) in tablet form, was chosen for this study. The first step was devoted to the evaluation of the intrinsic stability and the structural elucidation of the degradation products making use of LC-HR-MSn, providing access to the elemental composition. Degradation pathways have been proposed and the safety of the products has been evaluated via an in silico toxicological approach. Furthermore because antiplatelet agents are often used in combination therapy, in the second part, a preformulation strategy with aspirin in the solid state has been studied using the complementary techniques LC-HR-MSn, DSC, PXRD, and TGA. The mixture of the two active pharmaceutical ingredients gave rise to a simple eutectic. We have demonstrated that the degradation of ticagrelor in these mixtures is closely related to the stability of aspirin, which is modulated by environmental conditions. The ticagrelor study provides a model for the safety management of other drugs and can contribute to their appropriate recycling.
106

Hydrothermal processing of waste biomass: recovery of nutrients (N, P, soil amendments) and energy valorization

Scrinzi, Donato 18 July 2023 (has links)
Many environmental crises are threatening to collapse human societies, but also life on the Earth as we may know. Climate change due to anthropogenic global emissions is one of the main issues, but also soil degradation, and the management of the enormous amount of organic wastes that are harmfully released into the environment by human activities. On the one hand, direct spreading of biowastes onto the land is often limited due to eutrophication or pollution by toxic compounds. On the other hands, these biomasses may contain nutrients, such as phosphorus (listed as a critical raw material) and nitrogen, which could be recovered to sustain the high demand in expensive soil amendments and fertilizers. Thus, finding new solution to close the loop towards circular economy and sustainable processes is crucial, nowadays, to convert the global trends and restore the delicate equilibrium in the water-food-energy nexus, with soil ‘under special surveillance’. In this framework, many researchers are focusing their attention on hydrothermal carbonization (HTC) as a possible candidate, in particular to treat moist biowastes and obtain useful solid (hydrochar) and liquid (HTC liquor) products. Nutrients contained in biowastes are sensitive to HTC process parameters and initial feedstock properties, thus it is crucial to analyze their distribution and (im)mobilization among the HTC products for their reuse in soil. On the other hand, since some organic compounds are generated during the thermochemical process, which may be responsible for toxicity to plants and other organisms, analysis of their possible toxicity towards the biosphere becomes crucial before implementation at a large scale. This thesis collects our efforts to explore new processes and deepen the knowledge about the possibility to produce amendments suitable for soil application from hydrochar. The core is from a process engineering perspective, focusing on the production phase and the characterization of the products, never forgetting any possible limits or the implications on ecotoxicological issues. In the first part of the thesis, ‘How to make hydrochar a soil amendment?’ is the main question. Based on few pioneer studies about composting of hydrochar, we assessed a complete analysis of hydrochar co-compost, produced from the 25-day aerobic stabilization of digestate of organic fraction of municipal solid waste, together with a fraction of its hydrochar, and green waste. Under the umbrella of C2Land project (funded by The European Institute of Innovation & Technology -EIT), we produced this new amendment in specifically designed bioreactors, then we characterized the products from the point of view of physico-chemical properties, nutrients distribution, toxicity to plants and mammalian cells. We are confident that the crucial result of toxicity removal from hydrochar through composting will attract the interest of many stakeholders, since implementing HTC in anaerobic/aerobic plants is almost ready to be applied at a large scale. Moreover, an experimental campaign performed at the University of Leeds further explored the effect of some other post-treatments on hydrochar composition and phytotoxicity, depending on the initial feedstocks (manure, sewage digestate, water hyacinth, and grass). The second part of the thesis was dedicated to nutrients recovery, necessary when some harmful matrixes - such as the municipal sewage sludge digestate - are not allowed to be reused for agricultural purposes, due to law limitations or pollution issues. In this case, nutrients recovery (N, P) could be achieved chemically, via HTC and struvite precipitation, being struvite recognized as a good fertilizer. Firstly, we performed a techno-economic assessment of the implementation at a district level of HTC-centered sewage sludge management. The mass reduction of waste streams may have some important effects on transportation costs, while the recirculation of HTC liquor back to the anaerobic digestors can imply more biomethane production with increased revenues. A mass balance for the potential of N and P recovery through struvite precipitation in the centralized facility was also assessed. Secondly, a near-zero waste treatment process for municipal sewage sludge via HTC was designed according to the available literature and preliminarily analyzed at lab level. The fractionation of the different types of phosphorus was analyzed through the STM-P protocol before and after HTC, confirming the mineralization of organic phosphorus during the process. Citric acid was validated as a good green solvent for phosphorus extraction and high-quality struvite precipitation, even if the process was not still optimized in terms of yields. Future works may identify the best process parameters for final metal recovery from liquid byproducts in order to internally recirculate them back to water line, and to characterize the leached hydrochar as purified renewable fuel or soil amendment. Thus, the proof-of-concept chain would be confirmed and could be applied to the sustainable HTC-centered biorefineries of the future.
107

Avaliação dos aspectos toxicológicos dos fitoterápicos: um estudo comparativo / Evaluation of toxicological aspects of the herbal medicines:a comparative study

Turolla, Monica Silva dos Reis 13 April 2004 (has links)
Esta Dissertação apresenta informações gerais sobre os medicamentos fitoterápicos e os aspectos toxicológicos de uma amostra de dez plantas medicinais comercializadas como medicamentos fitoterápicos no Brasil, pesquisados junto aos principais bancos de dados e fontes públicas de informação. A análise dos medicamentos fitoterápicos cobre as dimensões histórica, econômica e farmacêutica. No tocante aos aspectos toxicológicos, foram avaliados os dados de toxicidade pré-clínica de dez plantas selecionadas, e realizado um levantamento das informações publicadas para Hypericum perforatum e Piper methysticum, relacionadas ao termo toxicidade, segundo três importantes bancos de dados. Adicionalmente, este trabalho aborda as propostas para realização de ensaios de toxicidade pré-clínica para os fitoterápicos segundo a OMS e legislação brasileira, e as normas para avaliação de substâncias químicas segundo a OECD. / This thesis presents general information on herbal medicines and on the toxicological aspects of a sample of ten medicinal plants traded as herbal medicines in Brazil. The survey was carried out in the main databases and public sources of information. The analysis on the herbal medicines encompasses the historical, economic and pharmaceutical dimensions. In what concerns toxicological aspects, data on pre-clinical toxicity were evaluated for Hypericum perforatum and Piper methysticum, these keywords being related to toxicity in three important databases. In addition, this study discusses the proposals for pre-clinical toxicity trials on herbal medicines according to WHO and the Brazilian legislation, and the standards for evaluation of chemical substances according to OECD.
108

Avaliação dos aspectos toxicológicos dos fitoterápicos: um estudo comparativo / Evaluation of toxicological aspects of the herbal medicines:a comparative study

Monica Silva dos Reis Turolla 13 April 2004 (has links)
Esta Dissertação apresenta informações gerais sobre os medicamentos fitoterápicos e os aspectos toxicológicos de uma amostra de dez plantas medicinais comercializadas como medicamentos fitoterápicos no Brasil, pesquisados junto aos principais bancos de dados e fontes públicas de informação. A análise dos medicamentos fitoterápicos cobre as dimensões histórica, econômica e farmacêutica. No tocante aos aspectos toxicológicos, foram avaliados os dados de toxicidade pré-clínica de dez plantas selecionadas, e realizado um levantamento das informações publicadas para Hypericum perforatum e Piper methysticum, relacionadas ao termo toxicidade, segundo três importantes bancos de dados. Adicionalmente, este trabalho aborda as propostas para realização de ensaios de toxicidade pré-clínica para os fitoterápicos segundo a OMS e legislação brasileira, e as normas para avaliação de substâncias químicas segundo a OECD. / This thesis presents general information on herbal medicines and on the toxicological aspects of a sample of ten medicinal plants traded as herbal medicines in Brazil. The survey was carried out in the main databases and public sources of information. The analysis on the herbal medicines encompasses the historical, economic and pharmaceutical dimensions. In what concerns toxicological aspects, data on pre-clinical toxicity were evaluated for Hypericum perforatum and Piper methysticum, these keywords being related to toxicity in three important databases. In addition, this study discusses the proposals for pre-clinical toxicity trials on herbal medicines according to WHO and the Brazilian legislation, and the standards for evaluation of chemical substances according to OECD.
109

Développement de seuils toxicologiques et prédiction de doses internes pour l’exposition professionnelle aux substances organiques à partir de leurs structures moléculaires

Chebekoue, Sandrine Fleur 08 1900 (has links)
No description available.
110

Aufbau und Anwendung einer Methode zur Identifizierung und Quantifizierung von Giften und deren Metaboliten in Blut und Haaren in der Systematischen Toxikologischen Analyse mittels Flüssigchromatographie-Quadrupol-Flugzeitmassenspektrometrie-Kopplung (LC-QTOF-MS)

Broecker, Sebastian 15 February 2012 (has links)
Die Systematische Toxikologische Analyse (STA) stellt auf Grund der großen Vielfalt und der ständigen Zunahme an toxikologisch relevanten Substanzen eine der größten Herausforderungen in der chemischen Analyse dar. In der vorliegenden Arbeit wurde daher die Eignung der Flüssigchromatographie in Kombination mit der Hybrid-Quadrupol-Flugzeitmassenspektrometrie (LC-QTOF-MS) für diesen Zweck untersucht. Dazu wurden eine Datenbank mit über 7360 und eine CID-Spektrenbibliothek mit mehr als 2720 toxikologisch relevanten Substanzen erstellt und geeignete Probenvorbereitungsmethoden entwickelt. Die Erprobung der Methoden erfolgte an dotierten Blut- und Haarproben. Hierbei zeigte sich, dass die Analyse im Auto-MS/MS-Modus (Messzyklen von MS- und MS/MS-Spektren) eine Identifizierung basischer Substanzen mittels CID-Spektren zwischen 0,5 und 2 ng/ml im Blut ermöglichte. Die Nachweisgrenzen der für 24 Wirkstoffe validierten Methode in Haaren lagen bei 3 bis 15 pg/mg. Die Eignung der LC-QTOF-MS zur STA von Haarproben wurde an 30 Drogentodesfällen und 60 Todesfällen mit bekannter chronischer Medikamenteneinnahme zu Lebzeiten sowie an 77 Blutproben nachgewiesen. Für die Suche nach Metaboliten wurde ein Metaboliten-Tool entwickelt. In der praktischen Anwendung auf Datenfiles von Blut- und Haarproben erwies sich das Tool als wertvolles Hilfsmittel zur Identifizierung unbekannter Peaks und zur Bestätigung von Suchergebnissen in der Datenbank. Zur automatischen Konzentrationsabschätzung identifizierter Substanzen wurde ein Tool „Estimate Concentration“ geschaffen. Die Überprüfung des Verfahrens an realen Blut- und Haarproben durch Vergleich mit HPLC-DAD- und GC-MS-Ergebnissen wies eine gute Übereinstimmung der Konzentrationen auf. Insgesamt zeigten die Untersuchungen, dass die LC-QTOF-MS zurzeit die am besten geeignete Methode für die STA darstellt. Auch bei einem erst später aufkommenden Verdacht kann eine gezielte Suche in dem bereits gemessenen Datenfile durchgeführt werden. / Due to the large variety and the steady increase of toxicologically relevant substances, systematic toxicological analysis (STA) is one of the most difficult tasks in analytical chemistry and, therefore, a steady topic of research and methodical improvement. For this reason, the suitability of liquid chromatography in combination with hybrid quadrupole time-of-flight mass spectrometry (LC-QTOF-MS) for STA was investigated. For this purpose, a database of more than 7360 and a CID spectra library of more than 2720 toxicologically relevant substances and suitable methods for sample preparation were developed. The application was evaluated at spiked blood and hair samples. It was found that the analysis in Auto-MS/MS mode (alternating measurement cycles of MS and MS/MS spectra) allowed substance identification in blood using CID spectra between 0.5 and 2 ng/ml for basic substances. The detection limits of the validated method in hair ranged from 3 to 15 pg/mg for 24 drugs. The suitability of LC-QTOF-MS for STA was tested for hair samples from 30 drug-related death cases and from 60 death cases with known chronic medication as well as for 77 blood samples. For the search of metabolites, a metabolite tool was developed. In the practical application to data files from blood and hair samples, the tool proved to be very helpful for identification of unknown peaks and for confirmation of results obtained only from the database without CID spectra. A tool "Estimate Concentration" was created for automatic estimation of concentrations of identified substances. The application to real blood and hair samples and the comparison of the concentrations with results from HPLC-DAD and GC-MS showed good agreement. Overall, these investigations showed that LC-QTOF-MS is currently the most favorable method for STA. Because of the comprehensive registration of all substances in a sample, the data files can be checked for the presence of certain poisons even later without new measurements.

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