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Foodways and Socioeconomic Complexities in Early Iron Age of Bara, Old Oyo, Nigeria (ca. 490 B.C. to A.D. 40)Oyundoyin, Racheal Bolakale 13 August 2024 (has links) (PDF)
The Early Iron Age period has been underexplored in the archaeology of West Africa, particularly Nigeria. Also, there is a lack of research and knowledge on organic residue analysis in Nigeria, particularly in the southwestern region of the country, despite the fact that other studies on archaeobotany and paleoenvironmental studies are well established. To address this gap, lipid analysis was conducted on 10 vessels from the Early Iron Age (490 B.C. to A.D. 40) site BSM6 in Bara, Old Oyo, Nigeria. The analysis revealed the plant and animal materials consumed by the Early Iron Age community. These findings provide vital insights into the dietary and subsistence practices of the period, illustrating continuities and changes in food practices from ancient to present times.
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Isolierung und Charakterisierung der Chitin-basierten Skelette der marinen Schwämme Aplysina cavernicola und Ianthella bastaUeberlein, Susanne 26 January 2016 (has links) (PDF)
Die Schwammskelette der Ordnung Verongida zeichnen sich durch das Fehlen mineralischer Komponenten aus. Stattdessen bestehen sie aus Spongin, einem kollagenartigen Protein, und Chitin. Im Rahmen der vorliegenden Arbeit wurden die aus solch einem Chitin-Protein-Komplex bestehenden Skelette der Schwammspezies Aplysina cavernicola und Ianthella basta aus der Ordnung Verongida untersucht. Aufgrund ihrer morphologischen Unterschiede wurde für jede Schwammart eine eigene Methode zur Isolierung der Schwammskelette entwickelt. Die isolierten Skelette konnten anschließend mit verschiedenen Methoden wie REM, ATR-FTIR-Spektroskopie und NMR-Spektroskopie charakterisiert werden.
Weiterhin wurde eine Methode zur Extraktion und Analyse der in den Skeletten befindlichen Aminosäuren mittels GC-MS entwickelt. Die Untersuchungen zeigten deutlich, dass es sich bei Spongin um ein kollagenartiges und halogeniertes Protein handelt, welches je nach Schwammart Unterschiede in der Aminosäurezusammensetzung aufweist. Darüber hinaus gelang es zum ersten Mal das Chitin aus dem Chitin-Protein-Komplex mittels Phosphorsäure zu entfernen. Aus den gewonnenen Erkenntnissen konnte abschließend ein Modell zum Aufbau des Chitin-Protein-Komplexes in der Schwammspezies Aplysina cavernicola entwickelt werden.
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Caratterizzazione della diversità microbica in fave di cacao fermentate / CHARACTERIZATION OF MICROBIAL BIODIVERSITY IN FERMENTED COCOA BEANSBORTOLINI, CRISTIAN 31 May 2017 (has links)
La qualità delle fave di cacao disponibili in commercio, che rappresentano la principale materia prima per la produzione di cioccolato, dipende da diversi fattori inclusi: il tipo di piantagione, le pratiche agricole ed il processo di post raccolta. Tra queste; fermentazione ed essicazzione sono generalmente considerate le più rilevanti, dal momento in cui, durante queste fasi, vengono formati e fissati i precursori degli aromi del cacao. Inoltre, esse rappresentano un step cruciale durante il quale possono verificarsi contaminazioni da parte dei funghi filamentosi. La fermentazione è caratterizzata da una successione ben definita di lieviti, batteri lattici e batteri acetici, a tal fine, lo scopo del presente lavoro di tesi è stato quello di esplorare e descrivere in modo completo le comunità batteriche e fungine coinvolte nella fermentazione delle fave di cacao e valutare se l’origine geografica ed il metodo di fermentazione potessero influenzare la loro composizione. Per ottenere tali risultati il gene 16s rRNA è stato usato come marker per descrivere la comunità batterica totale mediante High Throughput Sequencing (HTS), dimostrando come tale approccio abbia la capacità di evidenziare la totalità delle comunità batteriche a livello di specie. In un secondo approccio l’Internal Transcribed Spacer 1 (ITS1) ed il dominio D1/D2 della sub unità maggiore dell’RNA ribosomiale (26s rRNA) sono stati selezionati per descrivere la popolazione fungina. I risultati hanno evidenziato come le due regioni abbiano la capacità di descrivere la composizione generale delle popolazioni, sebbene il dominio D1/D2 sia stato in grado di analizzare più nel dettaglio la composizione. Infine gli stessi campioni sottoposti all’analisi mediante HTS sono stati analizzati mediante SPME-GC-MS per evidenziare i principali composti aromatici formatisi durante il processo di post raccolta.
Complessivamente i risultati indicano chiaramente che l’approccio mediante HTS ha le potenzialità per fornire una dettagliata visione d’insieme delle comunità batteriche e fungine presenti durante le fasi di post raccolta delle fave di cacao, inoltre le analisi statistiche hanno evidenziato come l’ITS1 ed i composti volatili possano essere utilizzati per la tracciabilità geografica. / The quality of commercial cocoa beans, the principal raw material for chocolate production, depends on several factors including type of plantations, the agricultural practices and the post-harvest processing. Among these, fermentation and drying are generally considered the most relevant, since during these phases cocoa flavors precursors are formed and fixed. Furthermore, they represent crucial steps during which filamentous fungi contamination might occur. Fermentation is characterized by a well-defined succession of yeasts, lactic acid bacteria and acetic acid bacteria, so that, the aim of the described studies was to explore total bacterial and fungal communities involved in cocoa bean fermentation and to evaluate if geographical origin and fermentation method might affect their composition. To achieve these results, 16s rRNA gene was used as marker to assess the total bacterial community by using High Throughput Sequencing (HTS), indicating that this approach has the ability to provide a comprehensive view of the cocoa bean microbiota at the species level. In a second approach, Internal Transcribed Spacer 1 (ITS1) and the D1/D2 domain of the Large subunit (LSU) of the nuclear ribosomal RNA (26S rRNA) were screened to assess the total fungal community. Results revealed the ability of these two genomic regions to describe reliably the general composition, even if D1/D2domain was able to go deeper into the fungal composition resulting in a higher resolution. In the last approach the same samples subjected to HTS investigation were analyzed through SPME-GC-MS in order to underline the principal key-aroma compounds formed during the post-harvest processing.
Overall, results point out clearly that HTS approach has the ability to provide a comprehensive view of the total bacterial and fungal communities, and statistical analyses have shown how analyses of ITS1 sequences and volatile compounds might be useful for the geographical traceability of the processed cocoa beans samples.
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Entwicklung einer Multimethode zur Probenaufarbeitung und Bestimmung von gas- und flüssigkeitschromatographisch erfassbaren Pestiziden in HühnereiernHildmann, Fanny 05 September 2016 (has links) (PDF)
Die Rückstandsanalytik tierischer Lebensmittel ist eine anspruchsvolle Aufgabe aufgrund des hohen Lipidanteils der Proben sowie des sich stetig vergrößernden Wirkstoffspektrums. Heutzutage werden für die Probenaufarbeitung die DFG S 19 Methode, mit der vorrangig unpolare Analyten nachgewiesen werden und zunehmend die QuEChERS Methode eingesetzt, die insbesondere auf die Erfassung polarer Pestizide abzielt.
In dieser Arbeit wurde eine moderne Multirückstandsmethode für Hühnereier entwickelt, um sowohl gas- als auch flüssigkeitschromatographisch (GC, LC) erfassbare Wirkstoffe zu analysieren. Dazu gehören unpolare PCBs, Pyrethroide und Organochlorpestizide, aber auch polarere Organophosphate, Triazole und Carbamate. Das Verfahren basiert auf der Extraktion mittels Matrix Solid Phase Dispersion, der Reinigung auf Grundlage einer modifizierten Gelpermeationschromatographie (GPC) und zwei verschiedenen Festphasenextraktionen (SPEs) für GC- und LC-erfassbare Pestizide sowie der Quantifizierung mittels GC- und LC-MS/MS.
Dünnschichtchromatographisch wurde die effektive Entfernung hochmolekularer Lipide durch die modifizierte GPC und niedrigmolekularer Fette durch die SPEs belegt. Laut der für Ei durchgeführten Validierung erfüllten 164 der 172 untersuchten Pestizide und alle sechs PCBs die Leistungskriterien für die amtliche Rückstandskontrolle - zumeist am niedrigsten validierten Level (5 µg/kg bzw. 0,5 µg/kg). Ausnahmen bildeten sehr polare LC-Pestizide (z.B. Aminopyralid, Clopyralid, MCPA, Quinmerac) und pH-Wert-abhängige GC-Analyten (Nicotin, Tolylfluanid, Dichlofluanid), die auch mit den etablierten Verfahren schwierig zu analysieren sind. Weiterhin verdeutlichte die erfolgreiche Untersuchung von verschiedenen Ringversuchsmaterialien, dass die ursprünglich für Eier entwickelte Methode auch für mageres Geflügelfleisch und Sahne genutzt werden kann.
Gegenüber den etablierten Verfahren wies die neue Methode deutliche Vorzüge auf. So belegte die Dünnschichtchromatographie, dass mit der neuen Methode Cholesterin, aber auch freie Fettsäuren besser abgetrennt werden als mit den etablierten Verfahren. Die neue Methode verbrauchte im Vergleich zur DFG S 19 Methode 46 % weniger Lösungsmittel und ermöglichte eine Verdopplung des Probendurchsatzes innerhalb von 8 h. Zudem eignete sich das entwickelte Verfahren laut den Validierungsdaten für GC-Analyten deutlich besser als die QuEChERS Methode und etwas besser als die DFG S 19 Methode (v.a. für Pyrethroide). Hinsichtlich der LC-Analyten unterschieden sich die neue und die QuEChERS Methode nur bei wenigen Analyten. Mit dem neuen Verfahren konnten folglich im Gegensatz zu den etablierten Methoden sowohl unpolare GC- als auch polare LC-Analyten sicher erfasst werden.
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Complexes pinceurs de cobalt et de nickel : synthèse, caratérisation, réactivitéLefèvre, Xavier 08 1900 (has links)
Plusieurs nouveaux complexes pinceurs de cobalt et de nickel ont été préparés avec le ligand pinceur de type POCOP : 2,6-(i-Pr2PO)2C6H4.
Dans le cas du cobalt, une nouvelle voie de synthèse a été développée. Contrairement au cas du nickel, il s’agit ici de cobalt au degré d’oxydation +III. Les composés obtenus sont paramagnétiques. En outre, le dérivé bromé est instable à la lumière et se décompose en perdant un brome pour former le complexe pinceur de Co(II). La réactivité de ces complexes a été étudiée.
Pour ce qui est du nickel, la catalyse de l’hydroamination a été élargie aux dérivés de l’acrylonitrile et aux amines aromatiques. En outre, la réaction d’hydroaryloxylation a été étudiée dans les mêmes conditions. Enfin, avec le 4-cyanostyrène et le cinnamonitrile, la formation d’amidines a été observée. Un complexe pinceur portant cette amidine a été isolé.
Enfin, le cation réagit avec des anions fortement coordonnants tels le cyanure ou l’isocyanate. En outre, l’anion triflate peut être déplacé par l’eau, l’acrylonitrile et ses dérivés. Enfin, une réactivité particulière a été observée avec la morpholine, l’acétone et un mélange 1:1 aniline/triéthylamine. / A large variety of new POCOP pincer type complexes of cobalt and nickel have been prepared. All those complexes are based on the following POCOP pincer type ligand: 2,6-(i-Pr2PO)2C6H4
In the case of cobalt, a new synthetic pathway has been developped. Unlike nickel, complexes containing cobalt in the +III oxidation state are obtained, the mechanism of their formation remains unknown. These complexes are paramagnetic. The dibromo derivative is light-sensitive, decomposing by losing a bromine to form the Co(II) pincer complex. The reactivity of those complexes has been studied.
Concerning nickel, the catalyzed hydroamination has been extended to the derivates of acrylonitrile, crotonitrile and methacrylonitrile and to aromatic amines. Moreover, hydroaryloxylation reaction has been studied under the same conditions. Finally, amidines formation was obtained with 4-cyanostyrene and with cinnamonitrile. A pincer complex bearing this amidine moiety has been isolated.
The cationic complex reacts with strong coordinating anions like cyanide and isocyanate. Moreover, the triflate anion is displaced by water, acrylonitrile and acrylonitrile derivates. Finally, a particular reactivity has been observed with morpholine, acetone and a 1:1 mixture of aniline and triethylamine.
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Oviposition cues as a tool for developing a new malaria control strategyEneh, Lynda January 2016 (has links)
Anopheles gambiae sensu lato mosquitoes are among the dominant malaria vectors in sub-Saharan Africa. However, not much is known about the oviposition behaviour of these species necessary for the development of malaria vector control strategies. With the aim of investigating cues associated with selected oviposition sites, artificial oviposition sites- ponds (soil mixed with water) were set-up in an open field at Mbita, Western Kenya in 2012 and 2013. Ponds were allowed to be colonized by wild An. gambiae s.l.. The numbers of Anopheles early instar larvae were counted and used as a proxy for oviposition preference. Water samples were then analysed for physicochemical, bacterial and chemical profiles. The bacterial profiles were analysed using denaturing gradient gel electrophoresis (DGGE) and the chemical profiles with gas chromatography-mass spectrometry (GC-MS). The detection of possible oviposition cues from oviposition substrates requires sensitive analytical methods. Volatiles detection was improved seven times. The detection of bacteria deoxyribonucleic acid (DNA) bands with DGGE was also improved to a minimum DNA concentration of 50 ng/µl. Results showed that ponds were colonized differently. Fresh ponds were preferred over slightly older ponds. Bacterial analysis revealed a low number of bacteria colony forming units (CFU) in preferred ponds. Some volatiles, including: 6,10-dimethyl-5,9-undecadien-2-one (geranylacetone) and 4-ethylbenzaldehyde, were associated with the oviposition preferred pond. In addition, low pH and high turbidity were associated with the ponds selected for oviposition. Finally, fungi isolated from the rhizomes of nut grass yielded a promising array of volatiles of which one is known to attract oviposition site seeking malaria mosquitoes. This finding opens the door for a cost effective and environmental friendly method of using fungi in an “attract and kill” strategy targeting malaria vectors. / Myggor i Anopheles gambiae sensu lato komplexet tillhör de myggor som är bäst på att sprida malaria parasiter i afrika söder om Sahara. Kunskapen om de här myggornas äggläggningsbeteende är begränsad. Den här kunskapen behövs för att kunna utveckla nya och förbättra tillgängliga malaria vektor kontroll metoder. Nya metoder som kan komplettera de som används idag (insecticides treated nets (ITNs) och indoor residual spraying (IRS)) behövs eftersom de metoderna har problem med resistensutveckling. Två studier utfördes på icipe fältstation i Mbita västra Kenya under 2012 och 2013 med målet att identifiera faktorer som påverkar myggornas äggläggningsbeteende. Baljor fyllda med en blandning av jord och vatten (äggläggningssubstrat) användes för att tillverka artificiella äggläggningsplatser som liknar de vattenpölar som de här myggarterna gärna lägger ägg i. Baljorna koloniserades av vilda myggor och antalet mygglarver som detekterades i baljorna jämfördes och användes som en proxy för äggläggningspreferens. Fysikaliska och kemiska parametrar mättes på jordvattenblandningarna i baljorna och prover togs för att analysera bakteriepopulationer med hjälp av denaturing gradient gel electrophoresis (DGGE) och flyktiga ämnen med hjälp av gas-kromatografi kopplat till mass-spektrometri (GC-MS). För att kunna detektera de låga halter av flyktiga ämnen och bakterier som fanns i de här proverna krävdes det känsliga metoder. Antalet flyktiga ämnen som kunde detekteras ökades sju gånger genom att tillsätta NaCl till vattenproverna innan doften insamlades och termisk desorption användes istället för lösningsmedels desorption. För att förbättra detektionsgränsen för bakterier amplifierades bakterie-DNA i två PCR reaktioner som sedan mixades och koncentrerades. Resultaten från fältstudierna med baljorna visade att de koloniserades olika av Anopheles myggorna. Baljor med nyblandat substrat innehöll dubbelt så många mygglarver som baljor med jord-vattensubstrat som åldrats under en längre tid. Lägre mängd bakterier, lägre pH och högre grumlighet var gemensamt för de baljor som myggorna föredrog. De flyktiga ämnen som detekterades i de olika baljor varierade mellan olika försök och inget ämne fanns med i alla upprepningar av ett försök. Trots det detekterades några ämnen oftare i de baljor som myggorna föredrog att lägga ägg jämfört med de med en mindre mängd mygglarver. De inkluderar geranylacetone och 4-ethylbenzaldehyde. Svampar isolerades från rotstockar av gräs som fanns i den jord som användes för att göra äggläggningssubstraten i fältstudierna. De flyktiga ämnen som avgavs från svampkulturerna analyserades. Bland annat så identifierades ett ämne som fungerar som en äggläggningsattrahent för An. gambiae s.l. myggor.Resultaten från den här avhandlingen kommer att kunna användas för att utveckla miljövänliga ”attract and kill” metoder för att kontrollera malaria myggor. / <p>QC 20160211</p>
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Avaliação da exposição ocupacional a praguicidas organofosforados em estufas de flores na região do Alto Tietê - São Paulo / Evaluation of occupational exposure to organophosphate pesticides in greenhouses of flower in the Alto Tietê region, state of S. Paulo, BrazilColasso, Camilla Gomes 12 September 2011 (has links)
O estado de São Paulo é responsável por 70% da produção nacional de flores e plantas ornamentais. Esses cultivos ocupam 7,5 mil hectares e mais da metade desta área é cultivada em estufas. Atualmente existem aproximadamente 8 mil produtores de pequeno, médio e grande porte em todo Brasil e este setor gera em torno de 200 mil empregos diretos, abrangendo produção e comércio. As estufas são microcosmos planejados para propiciar as condições ambientais adequadas ao crescimento de plantas. Qualquer infestação é controlada usando praguicidas que, devido ao enclausuramento e ajustes das condições climáticas, podem prolongar e intensificar a exposição ocupacional aos mesmos. Alguns estudos sugerem que os trabalhadores de estufas de flores e plantas ornamentais estão expostos a níveis mais elevados de praguicidas durante o carregamento, mistura e aplicação dos praguicidas, bem como pelo contato contínuo com as flores e plantas ornamentais, quando comparados a outros trabalhadores que entram em contato com essa classe de compostos. No presente trabalho, objetivou-se conhecer o processo de trabalho, práticas de saúde, higiene e segurança e localizar possíveis fontes de exposição ocupacional a praguicidas nas estufas de flores da região do Alto Tietê, e também otimizar métodos analíticos para a detecção e quantificação de praguicidas organofosforados (diclorvós, metil-paration e metidation) em patches de algodão e em tubos coletores XAD-2, com o intuito de analisar a exposição ocupacional dérmica e inalatória. O processo de avaliação incluiu o acompanhamento da jornada de trabalho, entrevistas e aplicação de questionários de trabalhadores de 18 estufas. Destas 18 foram selecionadas 6 estufas para coleta de amostras. Os organofosforados diclorvós, metidation e metilparation foram detectados e quantificados por cromatografia gasosa/espectrometria de massas (GC-MS), operado no modo de ionização por impacto de elétrons. Os dados da avaliação qualitativa demonstraram percentual elevado de desconhecimento das práticas adequadas de saúde, higiene e segurança para a utilização destes compostos, sugerindo que há risco de exposição durante a manipulação, armazenamento e descarte dos mesmos. Os limites de quantificação (LQ) obtidos foram abaixo de 0,4 ng/mL e limites de detecção (LD) foram abaixo de 0,1 ng/mL para todos os compostos. O método mostrou boa linearidade na concentração estudada (LSQ-500 ng/mL), com coeficiente (r) maior que 0,99. A precisão foi avaliada pelo desvio padrão relativo e apresentou valores inferiores a 15% para todos os compostos estudados. Após os métodos serem validados, foi realizada a amostragem dérmica e do ar e encontraram-se concentrações variadas de praguicidas. / The state of São Paulo - Brazil, accounts for 70% of domestic production of flowers and ornamental plants. Currently, these crops occupy 7.5 thousand hectares and over 50% of this area is cultivated in greenhouses. This market has an average of 8.000 producers and generates around 200.000 jobs. Greenhouses are microcosms designed to provide environmental conditions suitable for plant growth. Infestation is controlled using pesticides that due to the closure and adjustment to the weather conditions can prolong and intensify the exposure to them. Some studies suggest that workers in greenhouses of flowers and ornamental plants are exposed to higher levels of pesticides during loading, dilution and application, as well as by continuous contact with flowers and ornamental plants, when compared to other workers who enter in contact with this class of compounds. The aim of the present was to know the work process, to survey the practices of health, hygiene and safety standards and locate possible sources of occupational exposure to pesticides in greenhouses of flowers in the Alto Tietê region (São Paulo state), and to optimize analytical methods for detection and quantification of organophosphate pesticides (dichlorvos, methyl parathion and methidathion) in patches of cotton and in XAD-2 sorbent tubes, with the aim of analyzing the occupational dermal and inhalation exposure. The evaluation process included the monitoring of the working day, interviews and questionnaires, and samples collected in greenhouses. The organophosphorus compounds were detected and quantified by gas chromatography/mass spectrometry (GC-MS) operated in electron impact ionization. The data show a high percentage of lack of appropriate health practices, hygiene and safety for pesticide use suggests that there is risk of exposure during handling, storage and disposal of them. The limits of quantification (LOQ) obtained were below 0.4 ng/mL and limits of detection (LOD) were below 0.1 ng/mL for all compounds. The method showed good linearity in the studied concentration (LOQ-500 ng/mL), with coefficient (r) greater than 0.99. The precision was evaluated by relative standard deviation and showed values below 15% for all compounds studied. After the methods are validated, the dermal and air sampling was performed and a great range of pesticide concentrations was found. So it is evident that this study is valuable for future analysis and guidance to workers about possible hazards and proper use for reducing exposure to these compounds.
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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.
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Entwicklung von Analyseverfahren und Referenzmaterialien für die Bestimmung von Phenolen in umweltrelevanten MatricesLüders, Christian 12 October 1999 (has links)
Auf Basis moderner unabhängiger Analysenmethoden wurden selektive und spezifische Analysenverfahren für die Analytik von Phenolen, unter besonderer Berücksichtigung der Alkylphenole entwickelt, optimiert und teilweise validiert. Es wurden Verfahren für die Hochleistungs-Flüssigchromatographie - Massenspektrometrie (HPLC-MS), Hochleistungs-Flüssigchromatographie - Kernmagnetische Resonanzspektrometrie (HPLC-NMR), Gaschromatographie - Massenspektrometrie (GC-MS) und Kapillarelektrophorese (CE) entwickelt. Die HPLC-MS wurde mit den Atmosphärendrucktechniken "Electrospray Ionization" (HPLC-ESI-MS) und "Atmospheric Pressure Chemical Ionization" (HPLC-APCI-MS) eingesetzt. Die Gaschromatographie wurde in Kopplung zu einem hochauflösenden Massenspektrometer (GC-HRMS) und in Kopplung zu einem niederauflösenden Quadrupol-Spektrometer (GC-LRMS) verwendet. Mit der Kapillarelektrophorese wurden Verfahren in den Modi "Kapillar-Zonen-Elektrophorese (CZE) und "Micellare Electrokinetische Chromatographie (MEKC) mit verschiedenen internen Anreicherungstechniken ("Stacking") entwickelt. Für die Validierung des MEKC-Verfahrens mit interner Anreicherung ("Direktes-MEKC-Stacking") wurde ein Ringversuch organisiert und durchgeführt. Anhand von representativen Modellgemischen wurden die Verfahren geprüft und miteinander verglichen. Die Modellgemische sind reproduzierbar herstellbar; ihre Stabilität und Homogenität wurde abgesichert, so daß sie als synthetische Referenzmaterialien zur laborinternen Qualitätssicherung, zur Methodenbewertung und zum Laboratoriumsvergleich eingesetzt werden können. Anhand von charakteristischen Kenngrößen wie Bestimmungsgrenzen, Selektivität, Zeitaufwand, Kosten und Meßunsicherheiten wurden die Verfahren auf ihre Eignung als Standard- bzw. Referenzverfahren bewertet. Die Verfahren der HPLC-NMR, HPLC-ESI-MS, HPLC-APCI-MS und GC-HRMS können mit unterschiedlichem Einsatzbereich als Referenzverfahren für die Analytik von Phenolen eingesetzt werden. Die GC-HRMS ist dabei das leistungsstärkste Referenzverfahren. Die Verfahren der GC-LRMS und CE ("Direktes-MEKC-Stacking") sind als Standardverfahren geeignet und besitzen alle Voraussetzungen um auch als Normverfahren für die Analytik von Phenolen eingeführt zu werden. / Different selective and specific analysis procedures were developed for the determination of phenol derivatives, in particular alkylphenols, in environmental relevant matrices using High-Performance Liquid Chromatography - Mass Spectrometry (HPLC-MS), High-Performance Liquid Chromatography- Nuclear-Magnetic Resonance Spectrometry (HPLC-NMR), Gas Chromatography- Mass Spectrometry (GC-MS) and Capillary Electrophoresis (CE). HPLC-MS was used with atmospheric pressure ionization techniques, Electrospray Ionization (HPLC-ESI-MS) and Atmospheric Pressure Chemical Ionization (HPLC-APCI-MS). Analysis procedures for GC-MS were developed for a high resolution mass spectrometer (GC-HRMS) and a low resolution benchtop quadrupole mass spectrometer (GC-LRMS). CE was used in the Capillary Zone Electrophoresis (CZE) and Micellar Electrokinetic Chromatography (MEKC) mode with different internal stacking techniques. The MEKC procedure with internal stacking (called "Direct-MEKC-Stacking") was validated by an interlaboratory comparison test. These procedures were tested and optimized using representative model mixtures and the most efficient then validated. The model mixtures were produced reproducably and their stability and homogeneity were demonstrated for the application as synthetic reference materials, e.g. for internal laboratory control, quality assurance or method development. The different analysis procedures were categorized as standard- or reference procedures on the basis of characteristic properties, e.g. detection limits, selectivity, analysis time, cost and uncertainty. HPLC-NMR, HPLC-ESI-MS, HPLC-APCI-MS, GC-HRMS can be used as reference procedures for different fields of use. Best performance can be reached with GC-HRMS. GC-LRMS and "Direct-MEKC-Stacking" can be used as standard procedures for the analysis of phenol derivatives and they fulfill all conditions for their implementation in standardization.
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Análise de canabinóides e cocaínicos em amostras de cabelo e sua correlação com sintomas psiquiátricos / Analysis of cannabinoids and cocainics in hair samples and correlation with psychiatric symptomsAlves, Marcela Nogueira Rabelo 08 July 2015 (has links)
O consumo dos diferentes tipos de drogas está associado a problemas sociais, econômicos e de saúde pública, em todas as regiões no mundo. Dentre os problemas de saúde pública, podemos destacar a alta prevalência de comorbidade entre o uso de drogas e os transtornos mentais. A Cannabis, a cocaína e o crack são as drogas ilícitas mais consumidas no Brasil. A utilização do cabelo como matriz biológica para determinação destas drogas permite avaliar o uso crônicos pelos indivíduos, uma vez que o cabelo é uma matriz estável, de fácil manipulação e a janela de detecção depende apenas do comprimento do cabelo. Entretanto, a análise em cabelo ainda representa um desafio analítico. Foram desenvolvidos dois métodos para a detecção das diferentes drogas no cabelo, com diferentes enfoques analíticos. O primeiro método (desenvolvido durante o estágio de doutorado sanduíche na Itália) identificou e quantificou cocaína e metabólitos usando a técnica de column switching e detecção por LC-MS/MS. O segundo método foi desenvolvido para determinação de canabinóides nas amostras de cabelo utilizando GC-MS. O diferencial deste método foi a utilização de um novo dispositivo de extração em fase sólida (as ponteiras DPX) para concentração e purificação do extrato, utilizando menor quantidade de solventes. A determinação dos canabinóides e cocaínicos foi realizada nas amostras de cabelo da população atendida no CAPS - AD de Ribeirão Preto, São Paulo. Além da coleta da amostra de cabelo, o sujeito foi submetido a uma entrevista, onde os seguintes instrumentos de avaliação foram aplicadas: Questionário sobre a saúde do Paciente 9, Inventário de fobia social, Self Report Questionnaire, Questionário de Ansiedade de Beck, Inventário de Depressão de Beck e Questionário sobre o uso da Cannabis, bem como um questionário elaborado pelo pesquisador para coleta de dados sociodemográficos, consumo de substâncias e dados sobre a amostra de cabelo, como comprimento, cor, tintura ou coloração. As amostras de cabelo foram analisadas e a média das concentrações de cada droga encontrada no cabelo foi correlacionada com os indicadores clínicos de transtorno mentais, obtidos através dos instrumentos de avaliação psiquiátrica. A maior prevalência de indicadores clínicos positivos para transtornos psiquiátricos entre a população estudada foi de transtornos mentais comuns, entre eles a ansiedade e depressão. A comparação da média de concentração de Cannabis, cocaína e crack no cabelo com os indicadores clínicos positivos para os transtornos não apresentou resultados estatisticamente significantes. Entretanto, podemos inferir que os sujeitos que apresentaram maior concentração média de Cannabis e cocaína no cabelo possuíam mais indicadores clínicos positivos para sintomas mentais comuns e depressão maior enquanto que os sujeitos usuários de crack possuíam mais indicadores clínicos positivos para sintomas ansiedade. Apesar de algumas limitações, podemos concluir que o estudo possibilitou estimar a prevalência da morbidade entre abuso de drogas ilícitas e transtornos psiquiátricos na população atendida no Centro de Atenção Psicossocial Álcool e drogas de Ribeirão Preto. / Different kinds of drug use have been associated to social, economic and health public problems worldwide. Among the high prevalent public health problems is the comorbidity between drug abuse and psychiatric disorders. Cannabis, cocaine and crack are the most consumed illicit drugs in Brazil. Hair use as the biological matrix for the determination of these drugs allows to evaluate chronic use, once hair is a stable matrix, easy to manipulate and the window detection only depends on the size of the hair. However, hair analysis still represents an analytical challenge. It was developed two methods for the detection of the drugs in hair, with different analytical approach. The first method (developed during doctoral stage in Italy) had identified and quantified cocaine and metabolites using column switching technique and LCMS/ MS detection. The second method was developed for determination of cannabinoids in hair samples using GC-MS. Decontamination procedure was the same cited above. The differential of this method was the use of a new device in solid phase extraction (DPX tips) for the extracts concentration and purification, using less solvents volumes. Cannabinoids and cocaine analysis were performed in hair samples from people who were enrolled in the CAPS - AD of Ribeirão Preto, São Paulo. Besides hair collection, the individual was submitted to an interview, where it was applied the following evaluation scales: Patient health questionnaire - 9, Social phobia inventory, Self report questionnaire, Beck anxiety inventory, Beck depression inventory and Cannabis research questionnaire as well as a questionnaire made by the author to collect sociodemographic data, substance consume and hair data. Hair samples were analyzed and the concentrations were correlated with positive clinical factors of mental disorders obtained through evaluation scales. The highest prevalence of positive clinical indicators for psychiatric disorders among the population studied was of common mental disorders, including anxiety and depression. The comparison of the average concentration of Cannabis, cocaine and crack in the hair with the positive clinical indicators for the disorders did not show statistically significant results. However, we can infer that the subjects who had higher average concentration of Cannabis and cocaine in hair had showed positive indicators for common mental symptoms and major depression as well as the subjects who had higher average concentration of crack in hair had showed positive indicators for anxiety. Despite of some limitations, we can conclude that the study had allowed estimating the prevalence of morbidity among illicit drugs abuse and psychiatric disorders in the population enrolled in the psychosocial care center in Ribeirão Preto.
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