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

\"Desenvolvimento, otimização e validação da técnica HS-SPME-GC/MS para análise de amostras obtidas do Rio Atibaia através da aplicação de uma sistemática \"ISO\" para diagnóstico ambiental de áreas contaminadas\" / \"Development, optimization and validation of HS-SPME-GC/MS method for analysis of samples gotten from Atibaia River through the application of systematic \"ISO\" for environmental diagnosis of contamined areas\"

Olivares, Igor Renato Bertoni 18 December 2006 (has links)
Neste trabalho foi desenvolvida, otimizada, e validada, uma metodologia para análise de 15 pesticidas organoclorados em sedimento através de HS/SPME-GC/MS. Esta metodologia foi aplicada para análise de amostras reais visando à realização de um diagnóstico da contaminação por pesticidas organoclorados do Rio Atibaia, principalmente em sua região próxima a contaminação oriunda da empresa Shell Brasil S.A. unidade de Paulínia. Para realização deste diagnóstico, também foi desenvolvida uma metodologia padronizada para diagnóstico ambiental de áreas contaminadas, embasada principalmente em conceitos de Gestão de Qualidade e Meio Ambiente abordadas nas normas ISO 17025, ISO 14001 e GLP. Finalmente, aplicando a metodologia analítica validada, e a metodologia para realização de um diagnóstico ambiental, foi realizado o diagnóstico da presença de pesticidas organoclorados no Rio Atibaia, indicando a existência de diferentes pesticidas organoclorados em sedimento, com destaque para os compostos DDE e BHC que se encontraram em valores acima dos recomendados pela legislação canadense. Os resultados encontrados também demonstraram que as metodologias desenvolvidas foram adequadas para análise de uma contaminação real. / In this work a methodology was developed, optimized and validated for the analysis of 15 organochlorine pesticides in sediment through HS/SPME-GC/MS. This methodology was applied to the analysis of real samples for diagnosis of the organochlorine pesticides contamination of the Atibaia River, mainly in its region close the contamination from company Shell Brasil S.A. site of Paulínia. For accomplishment of this diagnosis, also a standard methodology for environmental diagnosis of contaminated areas was developed, mainly based in concepts of Quality Management and Environmental Management find in standards like ISO 17025, ISO 14001 and GLP. Finally, applying the validated analytical methodology and the methodology proposed for environmental diagnosis, the diagnosis of the organoclhorine pesticide presence in the Atibaia River was performed, indicating different organoclorine pesticides in sediment, mainly DDE and yBHC, which were found in values above of those recommended by the Canadian legislation. The results also demonstrated that the developed methodologies are adequate for analysis of a real contamination.
12

Desenvolvimento de métodos analíticos por cromatografia gasosa acoplada à espectrometria de massas para a identificação e quantificação de anatoxina-A em amostras de água e florações algais / Development of analytical methods by gas chromatography/mass spectrometry for anatoxin-a identification and quantification in water and algae bloom samples

Salazar, Vania Cristina Rodríguez 19 January 2007 (has links)
A poluição dos corpos d\'água é de grande preocupação mundial, pois a maioria da população utiliza a água doce de reservatórios, represas ou rios como principal fonte de água potável. A presença no Brasil de florações de cianobactérias capazes de produzir anatoxina-a, revela a necessidade de métodos simples e rápidos que permitam sua detecção e monitoramento. Neste trabalho foram desenvolvidos, otimizados e validados dois métodos analíticos por GC/MS para identificação e quantificação de anatoxina-a em amostras de água e florações, respectivamente. A norcocaína foi usada como padrão interno em ambos os métodos. Os íons escolhidos para serem monitorados foram (íons quantificadores sublinhados): anatoxina-a: 191,164, 293 e norcocaína: 195, 136, 168. As curvas de calibração dos métodos mostraram-se lineares nas faixas de 2.5-200 ng.mL-1 e 13-250 ng.mg-1. Os limites de detecção obtidos foram 2 ng.mL-1 e 10 ng.mg-1. Os métodos demonstraram sensibilidade e especificidade adequada para seu uso no monitoramento ambiental da anatoxina-a. / The water pollution is a big concern around the world, since the most of cities use freshwater reservoirs, dams or rivers as the main drinking water suppliers. Cyanobacterial blooms capable to produce anatoxin-a are regularly present in Brazilian waters. Therefore, there is a necessity of simple and rapid analytical methods to monitor this cyanotoxin. In the present work, two analytical methods by GC/MS for identification and quantification of anatoxin-a in water and algae bloom samples were developed, optimized and validated. Norcocaine was used as internal standard in both methods. The ions chosen to be monitorated were (quantification ions underlined): anatoxin-a 191, 164, 293 and norcocaine: 195, 136, 168. Both method calibration curves showed linearity in the ranges of: 2.5-200 ng.mL-1 and 13-250 ng.mg-1. The obtained limit of detection were: 2 ng.mL-1 and 10 ng.mg-1. The methods showed sensitivity and specificity enough to be used routinely as a tool for anatoxin-a monitoring.
13

Avaliação de modelos microbiológicos e modelos biomiméticos no metabolismo estereosseletivo da risperidona por cromatografia líquida de alta eficiência / Evaluation of microbiological and biomimetic models in stereoselective metabolism of risperidone by high-performance liquid chromatography

Bocato, Mariana Zuccherato 02 August 2012 (has links)
A risperidona é um medicamento antipsicótico que quando metabolizada da origem a dois metabólitos hidroxilados quirais, a 7-hidroxirisperidona (7-RispOH) e a 9-hidroxirisperidona (9-RispOH). A 9-RispOH apresenta as mesmas propriedades farmacológicas que a risperidona e já é comercializada como fármaco, com o nome genérico de paliperidona. Estudos em humanos mostram que existem diferenças na disposição cinética dos enantiômeros da 9-RispOH, com uma maior prevalência do enantiômero (+)-9-RispOH em plasma. Dessa forma, este trabalho teve como finalidade avaliar a capacidade de algumas espécies de fungos e também de catalisadores de Jacobsen em (bio)transformar enantiosseletivamente a risperidona em seu metabólito ativo 9-RispOH. Para tanto, foi desenvolvido um método de separação para a risperidona e seus metabólitos utilizando cromatografia líquida de alta eficiência quiral. Este método foi então aplicado nos estudos de biotransformação enantiosseletivo e nos estudos de catálise assimétrica. A separação cromatográfica foi realizada empregando a coluna Chiralcel OJ-H e metanol:etanol (50:50, v/v) + 0,2% de trietilamina como fase móvel. A vazão e temperatura utilizadas foram 0,8 mL min-1 e 25oC, respectivamente. Para extração dos analitos do meio de cultura, foi empregada a microextração em fase sólida (SPME) como técnica de preparação de amostra. O processo de SPME foi realizado utilizando uma fibra C18 mergulhando diretamente a fibra na amostra por 30 minutos e dessorvendo a fibra diretamente na fase móvel por 5 minutos. A validação e estudos de biotransformação foram realizados empregando a cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS). O método foi validado e todos os parâmetros encontram-se de acordo com as recomendações da literatura. O estudo de biotransformação foi realizado com diferentes espécies de fungos e somente os fungos do gênero Cunninghamella foram capazes de biotransformar a risperidona em seu metabólito ativo. O fungo Cunninghamella echinulata foi capaz de biotransformar estereosseletivamente a risperidona no seu metabólito ativo (+)-9-RispOH com excesso enantiomérico de 100% e o fungo Cunninghamella elegans foi também capaz de biotransformar estereosseletivamente a risperidona nos dois enantiômeros da 9-RispOH em diferentes proporções. Os estudos preliminares de catálise assimétrica foram realizados empregando a cromatografia líquida e detecção por UV-Vis, injetando diretamente alíquotas no sistema cromatográfico. Esses estudos mostraram que na condição de reação 1:50:50 (em número de mols, catalisador:oxidante:substrato) houve uma catálise assimétrica da risperidona que demonstrou ser enantiosseletiva para o metabólito 7-RispOH (E1). / Risperidone is an atypical antipsychotic drug. Its metabolism yields in two hydroxylated chiral metabolites, 7-hydroxyrisperidone (7-RispOH) and 9-hydroxyrisperidone (9-RispOH). The 9-RispOH metabolite presents the same pharmacologic activity of the parent drug risperidone. This led this drug to be marketed as drug under the generic name paliperidone. Studies have shown differences in the kinetic disposition of the 9-RispOH enantiomers with higher prevalence of the (+)-9-RispOH enantiomer in plasma. Thus, this work aimed to evaluate the ability of some species of fungi and Jacobsen catalysts in the enantioselective (bio)transformation of risperidone into its active chiral metabolite 9-RispOH. To accomplish that, it was developed a separation method to analyze risperidone and its metabolites by chiral high-performance liquid chromatography. This method was employed in enantioselective biotransformation studies and in asymmetric catalysis studies. The chromatographic separation was performed on a Chiralcel OJ-H column using methanol:ethanol (50:50, v/v) plus 0.2% triethylamine as the mobile phase at a flow rate of 0.8 mL min-1. The SPME process was performed by immersing directly a C18 probe fiber in the culture medium during 30 min. The analytes were desorbed from the fiber directly in the mobile phase during 5 min. The method validation and the biotransformation studies were performed by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The method was completely validated and all parameters were in agreement with the literature recommendations. The biotransformation studies were performed employing different species of fungi and only the Cunninghamella genus was able to biotransform risperidone into its active metabolite. The Cunninghamella echinulata fungus was able to biotransform risperidone into the active metabolite, (+)-9-RispOH, resulting in 100% of enantiomeric excess. The Cunninghamella elegans fungus was also able to biotransform stereoselectively risperidone into (+)- and ()-9-RispOH enantiomers at different rates. Preliminary studies of asymmetric catalysis were performed using high-performance liquid chromatography with UV-Vis detector (HPLC-UV). The aliquots were directly injected in the chromatography system. These studies showed that the reaction with 1:50:50 (catalyst:oxidant:substrate, in number of mols, in this sequence) presented an asymmetric catalysis of risperidone and that showed to be enantioselective to 7-RispOH (E1) metabolite.
14

Fibras para SPME (Microextração em fase sólida) recobertas com sílica modificadas por grupos vinila / Fibers for SPME (Solid Phase Microextraction) coated with modified silica vinyl groups

Batista, Alex Domingues 17 August 2018 (has links)
Orientador: Fabio Augusto / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-17T12:13:43Z (GMT). No. of bitstreams: 1 Batista_AlexDomingues_M.pdf: 1225711 bytes, checksum: 108d27c49f0c885f3e6b3f3302d1efc7 (MD5) Previous issue date: 2010 / Resumo: No trabalho estudou-se o preparo de fibras para Microextração em Fase Sólida (SPME) com recobrimentos baseados em sílicas organicamente modificadas através de processo sol-gel. O modificador utilizado foi o viniltriemetoxisilano para a obtenção de um revestimento inicial que posteriormente foi recoberta com poliestireno através da polimerização de monômeros de estireno catalisada por luz ultravioleta. As fibras foram caracterizadas química e morfologicamente através de Microscopia Eletrônica de Varredura, Espectroscopia no Infravermelho e Análise Termogravimétrica. Os recobrimentos apresentaram uma estrutura compacta, sem a presença visível de poros com uma espessura de 97 mm. Eles se apresentaram estáveis termicamente até uma temperatura de aproximadamente 320°C. As fibras foram utilizadas com sucesso na quantificação de BTEX em água de torneira, as curvas analíticas obtidas apresentaram coeficientes de correlação linear acima de 0,99. Os limites de detecção calculados pela curva analítica foram para benzeno, tolueno, etilbenzeno e o-xileno foram respectivamente 0,023, 0,042, 0,027 e 0,061 mg.L. As novas fibras foram utilizadas também na quantificação de androstenona e escatol em toucinho suíno onde também observado um coeficiente de correlação linear para a curva analítica acima de 0,99. Os limites de detecção foram 0,003 mg.g para androstenona e 0,009 mg.g para escatol / Abstract: In this work we studied the preparation of fibers for Solid Phase Microextraction (SPME) with coatings based on organically modified silica via sol-gel process. Vinyltrimethoxysilane was used as modifier for obtaining an initial coat that was later covered with polystyrene by polymerizing styrene monomers catalyzed by ultraviolet light. The fibers were characterized chemically and morphologically by scanning electron microscopy, infrared spectroscopy and thermogravimetric analysis. The coatings had a compact structure without the visible presence of pores with a thickness of 97 micrometers. They showed thermal stability up to a temperature of about 320°C. The fibers were successfully used in the quantification of BTEX in tap water, the analytical curves showed correlation coefficients above 0.99. The detection limits were calculated by the analytical curve of benzene, toluene, ethylbenzene and o-xylene were respectively 0.023, 0.042, 0.027 and 0.061 mg.L. The new fibers were also used for quantification of skatole and androstenone in pig fat which also observed a linear correlation coefficient for the calibration curve above 0.99. The detection limits were 0.003 mg.g for androstenone and 0.009 mg.g for skatole / Mestrado / Quimica Analitica / Mestre em Química
15

Avaliação de modelos microbiológicos e modelos biomiméticos no metabolismo estereosseletivo da risperidona por cromatografia líquida de alta eficiência / Evaluation of microbiological and biomimetic models in stereoselective metabolism of risperidone by high-performance liquid chromatography

Mariana Zuccherato Bocato 02 August 2012 (has links)
A risperidona é um medicamento antipsicótico que quando metabolizada da origem a dois metabólitos hidroxilados quirais, a 7-hidroxirisperidona (7-RispOH) e a 9-hidroxirisperidona (9-RispOH). A 9-RispOH apresenta as mesmas propriedades farmacológicas que a risperidona e já é comercializada como fármaco, com o nome genérico de paliperidona. Estudos em humanos mostram que existem diferenças na disposição cinética dos enantiômeros da 9-RispOH, com uma maior prevalência do enantiômero (+)-9-RispOH em plasma. Dessa forma, este trabalho teve como finalidade avaliar a capacidade de algumas espécies de fungos e também de catalisadores de Jacobsen em (bio)transformar enantiosseletivamente a risperidona em seu metabólito ativo 9-RispOH. Para tanto, foi desenvolvido um método de separação para a risperidona e seus metabólitos utilizando cromatografia líquida de alta eficiência quiral. Este método foi então aplicado nos estudos de biotransformação enantiosseletivo e nos estudos de catálise assimétrica. A separação cromatográfica foi realizada empregando a coluna Chiralcel OJ-H e metanol:etanol (50:50, v/v) + 0,2% de trietilamina como fase móvel. A vazão e temperatura utilizadas foram 0,8 mL min-1 e 25oC, respectivamente. Para extração dos analitos do meio de cultura, foi empregada a microextração em fase sólida (SPME) como técnica de preparação de amostra. O processo de SPME foi realizado utilizando uma fibra C18 mergulhando diretamente a fibra na amostra por 30 minutos e dessorvendo a fibra diretamente na fase móvel por 5 minutos. A validação e estudos de biotransformação foram realizados empregando a cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS). O método foi validado e todos os parâmetros encontram-se de acordo com as recomendações da literatura. O estudo de biotransformação foi realizado com diferentes espécies de fungos e somente os fungos do gênero Cunninghamella foram capazes de biotransformar a risperidona em seu metabólito ativo. O fungo Cunninghamella echinulata foi capaz de biotransformar estereosseletivamente a risperidona no seu metabólito ativo (+)-9-RispOH com excesso enantiomérico de 100% e o fungo Cunninghamella elegans foi também capaz de biotransformar estereosseletivamente a risperidona nos dois enantiômeros da 9-RispOH em diferentes proporções. Os estudos preliminares de catálise assimétrica foram realizados empregando a cromatografia líquida e detecção por UV-Vis, injetando diretamente alíquotas no sistema cromatográfico. Esses estudos mostraram que na condição de reação 1:50:50 (em número de mols, catalisador:oxidante:substrato) houve uma catálise assimétrica da risperidona que demonstrou ser enantiosseletiva para o metabólito 7-RispOH (E1). / Risperidone is an atypical antipsychotic drug. Its metabolism yields in two hydroxylated chiral metabolites, 7-hydroxyrisperidone (7-RispOH) and 9-hydroxyrisperidone (9-RispOH). The 9-RispOH metabolite presents the same pharmacologic activity of the parent drug risperidone. This led this drug to be marketed as drug under the generic name paliperidone. Studies have shown differences in the kinetic disposition of the 9-RispOH enantiomers with higher prevalence of the (+)-9-RispOH enantiomer in plasma. Thus, this work aimed to evaluate the ability of some species of fungi and Jacobsen catalysts in the enantioselective (bio)transformation of risperidone into its active chiral metabolite 9-RispOH. To accomplish that, it was developed a separation method to analyze risperidone and its metabolites by chiral high-performance liquid chromatography. This method was employed in enantioselective biotransformation studies and in asymmetric catalysis studies. The chromatographic separation was performed on a Chiralcel OJ-H column using methanol:ethanol (50:50, v/v) plus 0.2% triethylamine as the mobile phase at a flow rate of 0.8 mL min-1. The SPME process was performed by immersing directly a C18 probe fiber in the culture medium during 30 min. The analytes were desorbed from the fiber directly in the mobile phase during 5 min. The method validation and the biotransformation studies were performed by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The method was completely validated and all parameters were in agreement with the literature recommendations. The biotransformation studies were performed employing different species of fungi and only the Cunninghamella genus was able to biotransform risperidone into its active metabolite. The Cunninghamella echinulata fungus was able to biotransform risperidone into the active metabolite, (+)-9-RispOH, resulting in 100% of enantiomeric excess. The Cunninghamella elegans fungus was also able to biotransform stereoselectively risperidone into (+)- and ()-9-RispOH enantiomers at different rates. Preliminary studies of asymmetric catalysis were performed using high-performance liquid chromatography with UV-Vis detector (HPLC-UV). The aliquots were directly injected in the chromatography system. These studies showed that the reaction with 1:50:50 (catalyst:oxidant:substrate, in number of mols, in this sequence) presented an asymmetric catalysis of risperidone and that showed to be enantioselective to 7-RispOH (E1) metabolite.
16

\"Desenvolvimento, otimização e validação da técnica HS-SPME-GC/MS para análise de amostras obtidas do Rio Atibaia através da aplicação de uma sistemática \"ISO\" para diagnóstico ambiental de áreas contaminadas\" / \"Development, optimization and validation of HS-SPME-GC/MS method for analysis of samples gotten from Atibaia River through the application of systematic \"ISO\" for environmental diagnosis of contamined areas\"

Igor Renato Bertoni Olivares 18 December 2006 (has links)
Neste trabalho foi desenvolvida, otimizada, e validada, uma metodologia para análise de 15 pesticidas organoclorados em sedimento através de HS/SPME-GC/MS. Esta metodologia foi aplicada para análise de amostras reais visando à realização de um diagnóstico da contaminação por pesticidas organoclorados do Rio Atibaia, principalmente em sua região próxima a contaminação oriunda da empresa Shell Brasil S.A. unidade de Paulínia. Para realização deste diagnóstico, também foi desenvolvida uma metodologia padronizada para diagnóstico ambiental de áreas contaminadas, embasada principalmente em conceitos de Gestão de Qualidade e Meio Ambiente abordadas nas normas ISO 17025, ISO 14001 e GLP. Finalmente, aplicando a metodologia analítica validada, e a metodologia para realização de um diagnóstico ambiental, foi realizado o diagnóstico da presença de pesticidas organoclorados no Rio Atibaia, indicando a existência de diferentes pesticidas organoclorados em sedimento, com destaque para os compostos DDE e BHC que se encontraram em valores acima dos recomendados pela legislação canadense. Os resultados encontrados também demonstraram que as metodologias desenvolvidas foram adequadas para análise de uma contaminação real. / In this work a methodology was developed, optimized and validated for the analysis of 15 organochlorine pesticides in sediment through HS/SPME-GC/MS. This methodology was applied to the analysis of real samples for diagnosis of the organochlorine pesticides contamination of the Atibaia River, mainly in its region close the contamination from company Shell Brasil S.A. site of Paulínia. For accomplishment of this diagnosis, also a standard methodology for environmental diagnosis of contaminated areas was developed, mainly based in concepts of Quality Management and Environmental Management find in standards like ISO 17025, ISO 14001 and GLP. Finally, applying the validated analytical methodology and the methodology proposed for environmental diagnosis, the diagnosis of the organoclhorine pesticide presence in the Atibaia River was performed, indicating different organoclorine pesticides in sediment, mainly DDE and yBHC, which were found in values above of those recommended by the Canadian legislation. The results also demonstrated that the developed methodologies are adequate for analysis of a real contamination.
17

Desenvolvimento de métodos analíticos por cromatografia gasosa acoplada à espectrometria de massas para a identificação e quantificação de anatoxina-A em amostras de água e florações algais / Development of analytical methods by gas chromatography/mass spectrometry for anatoxin-a identification and quantification in water and algae bloom samples

Vania Cristina Rodríguez Salazar 19 January 2007 (has links)
A poluição dos corpos d\'água é de grande preocupação mundial, pois a maioria da população utiliza a água doce de reservatórios, represas ou rios como principal fonte de água potável. A presença no Brasil de florações de cianobactérias capazes de produzir anatoxina-a, revela a necessidade de métodos simples e rápidos que permitam sua detecção e monitoramento. Neste trabalho foram desenvolvidos, otimizados e validados dois métodos analíticos por GC/MS para identificação e quantificação de anatoxina-a em amostras de água e florações, respectivamente. A norcocaína foi usada como padrão interno em ambos os métodos. Os íons escolhidos para serem monitorados foram (íons quantificadores sublinhados): anatoxina-a: 191,164, 293 e norcocaína: 195, 136, 168. As curvas de calibração dos métodos mostraram-se lineares nas faixas de 2.5-200 ng.mL-1 e 13-250 ng.mg-1. Os limites de detecção obtidos foram 2 ng.mL-1 e 10 ng.mg-1. Os métodos demonstraram sensibilidade e especificidade adequada para seu uso no monitoramento ambiental da anatoxina-a. / The water pollution is a big concern around the world, since the most of cities use freshwater reservoirs, dams or rivers as the main drinking water suppliers. Cyanobacterial blooms capable to produce anatoxin-a are regularly present in Brazilian waters. Therefore, there is a necessity of simple and rapid analytical methods to monitor this cyanotoxin. In the present work, two analytical methods by GC/MS for identification and quantification of anatoxin-a in water and algae bloom samples were developed, optimized and validated. Norcocaine was used as internal standard in both methods. The ions chosen to be monitorated were (quantification ions underlined): anatoxin-a 191, 164, 293 and norcocaine: 195, 136, 168. Both method calibration curves showed linearity in the ranges of: 2.5-200 ng.mL-1 and 13-250 ng.mg-1. The obtained limit of detection were: 2 ng.mL-1 and 10 ng.mg-1. The methods showed sensitivity and specificity enough to be used routinely as a tool for anatoxin-a monitoring.
18

Développement d’un système de prélèvement de poussières pour la mise en place d’un outil alternatif de caractérisation de l’exposition humaine aux polluants organiques et aux métaux à la place du biomonitoring / Development of a dust collection system for the implementation of an alternative tool for characterizing human exposure to organic pollutants and metals in the place of biomonitoring

Sonnette, Alexandre 27 November 2017 (has links)
Un système de prélèvement de poussière a été mis au point pour étudier l’exposition des personnes aux polluants de l’air intérieur au moyen de prélèvements environnementaux plutôt que par le biomonitoring, plus contraignant. Une nouvelle méthode d’analyse de polluants de l’air intérieur par GC-MSMS a également été développée et permet la quantification d’une centaine de composés organiques dans l’air, dans la poussière, dans la salive et dans les cheveux. Ces deux développements ont été mis à l’épreuve lors d’une étude exploratoire réalisée sur une dizaine de logements en Alsace. Des prélèvements d’air, de poussière, de salive et de cheveux ont été effectués chaque mois chez des particuliers durant un an. Les résultats d’analyses ont été croisés avec les réponses d’un questionnaire sur l’habitat et les habitudes de vie rempli par les participants, et un traitement statistique a été réalisé dans le but de dégager des corrélations entre les différentes matrices. Il s’avère que s’il est aisé d’établir des corrélations entre matrices biologiques et environnementales pour les composés dont l’exposition est majoritairement domestique, comme par exemple pour certains pesticides, ce n’est pas le cas pour les polluants non-spécifiques au logement. Cette étude préliminaire a montré des résultats prometteurs, et ouvre la voie à une campagne de mesure à plus grande échelle visant à mettre en place un modèle statistique d’exposition domestique à des composés organiques. / A dust sampling device was developed to assess exposure to indoor air pollutants using environmental samples instead of biomonitoring, which is less practical. A new GC-MSMS analytical method was also developed to quantify one hundred indoor pollutants in dust, air, saliva and hair. Both developments were tested during an exploratory study taking place in Alsatian dwellings. Air, dust, saliva and hair samples were collected each month during one year in these dwellings. Results were crossed with the answers of the residents to a questionnaire about their house and living habits, and statistical data processing was performed with the aim of revealing correlations between environmental and biological matrices. It turns out its easy to establish intra-matrices correlations for compounds exclusively found in the house, like some pesticides, but not for compounds that are non-specifics to the dwelling. This preliminary study shows encouraging results, and paves the way to a large scale study aiming the development of a statistical model of exposure to organic compounds.
19

Detecting drugs of abuse in human breast milk using biocompatible solid phase microextraction and direct analysis in real time mass spectrometry

Woods, Emily Rae 31 January 2022 (has links)
Human breast milk is a biofluid produced by a woman’s body during pregnancy. Breast milk contains necessary nutrition to a growing infant as well as xenobiotics--including drugs of abuse-- consumed by the woman which diffuse into the breast milk from the bloodstream. Since breast milk is recommended to be part of all infants’ diets, being able to detect any toxic components--such as drugs--in the matrix is critical. However, despite the ease and noninvasive nature of collection, human breast milk is a difficult matrix to analyze due to its high fat and protein content. Thus far, no literature has been published on the analysis of breast milk through direct analysis in real time mass spectrometry (DART-MS). Adapting DART-MS to detect drugs of abuse in human breast milk will allow for quick and timely identification of drugs present in an individual’s breast milk, as well as aid in research regarding the potential harmful effects of drugs--both licit and illicit--on an infant who is breastfeeding. Forensically, this method could potentially allow toxicologists to use breast milk as a matrix to determine if drugs played a role in a woman’s or breastfed child’s death. Using both C18 biocompatible solid-phase microextraction (BIO-SPME) fibers and QuickStrip™ cards, a DART-MS method was developed to be able to detect drugs of abuse in human breast milk. Four drugs of abuse (cocaine, codeine, morphine, and delta-9-tetrahydrocannabinol (Δ9-THC))--all of which are either commonly abused during the postpartum period or are of particular danger to breastfeeding women--were chosen to be studied. The drugs of abuse were extracted from either whole or pre-filtered human breast milk using either liquid-liquid extraction or C18 BIO-SPME fibers and detected with DART-MS using parameters suggested by IonSense, Incorporation (Inc.). Mass spectral results indicated that macromolecules in whole breast milk did not hinder extraction or detection and that a larger amount of the analytes were ionized/desorbed when using the BIO-SPME fibers. Thus, a BIO-SPME method adopted from IonSense, Inc. utilizing C18 fibers and SPME DART-MS parameters (with temperature and rail time adjustments) can be used to quickly detect cocaine, codeine, morphine, and Δ9-THC in human breast milk, indicating that this method may be used for the detection of other drugs of abuse in breast milk. In addition, BIO-SPME fibers can be used to quantify the concentration of cocaine in breast milk between a range of 50 and 200 nanograms per milliliter as demonstrated by a matrix-matched calibration curve created using various concentrations of cocaine. Despite its benefits, the BIO-SPME and DART method cannot be used on samples containing more than one drug of abuse (based upon the drug concentrations utilized in this study) due to competitive adsorption and competitive ionization, respectively, as not all drugs could be detected when this method was applied to breast milk samples containing numerous drugs.
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In-Tip Solid Phase Microextraction for High Throughput Drug Analysis

Xie, Wei 12 September 2011 (has links)
This thesis describes the design of a convenient format of solid phase microextraction (SPME) for bioanalysis in pharmaceutical industry and the validation of the approach to the application. An automated in-tip SPME technique coupled with liquid chromatography (LC) and tandem mass spectrometry (MS/MS) for high throughout drug analysis has been developed and applied to the quantitative determination of various drug compounds in different biological fluids from drug discovery to clinical development. The initial research in this thesis focused on a proof-of-concept study using manual multi-fiber approach to determine a drug compound in human plasma from a clinical trial. The proof-of-concept was achieved based on the validation data and a head-to-head comparison with conventional liquid-liquid extraction (LLE) method. An in-tip SPME technique was then proposed to explore the feasibility of SPME automation and two approaches of preparing in-tip SPME fibers were developed including fiber-packed and sorbent-packed fiber preparation. A simple and high throughput in-tip SPME fiber fabricating procedure based on polymer monoliths using photo-polymerization was introduced to prepare 96 fibers simultaneously. The biggest advantage of the in-tip SPME technique is that it is simple and easy to use for automation without introducing any additional devices and in the meantime, the simplicity of SPME is maintained. Automated in-tip SPME was applied to routine drug analysis in drug discovery and development environment. One case study involved the determination of vitamin D3 in human serum with derivatization and the in-tip SPME approach was compared with traditional LLE method using either tubes or 96-well plate extraction. Another study was to use hydrophilic interaction chromatography (HILIC) –MS/MS to determine three polar compounds, imipenem (IMP), cliastatin (CIL) and -lactamase inhibitor (BLI) simultaneously in different biological fluids including rat plasma and mouse blood. The results from both studies clearly demonstrated that in-tip SPME could be used as an alternative sample preparation method in bioanalytical analysis. Matrix effects in bioanalysis using automated in-tip SPME and LC-MS/MS were then thoroughly evaluated for the first time. Our study indicated that the assumption that SPME should provide sample clean up as effective as or better than solid phase extraction (SPE) with no or minimal matrix effects might not be always true, and matrix effects should be investigated in any SPME assays in bioanalysis. Comparisons between in-tip SPME and other automated SPME approaches such as blade/thin film geometries were performed, and the advantages and limitations of using SPME versus conventional sample preparation methods including protein precipitation (PPT), LLE and SPE were summarized. Strategies for in-tip SPME method development and validation and the potential applications and future directions of in-tip SPME in bioanalysis were discussed. Finally, kinetic models were established to describe SPME extraction and desorption processes in a complex matrix with both liquid and solid fiber coatings. The models were successfully applied to different scenarios to estimate the boundary layer (BL) thickness, extraction equilibrium time and total amount of analytes extracted at a given time. The excellent agreements between the model prediction results and experimental data indicated that the SPME modeling approach had great potentials to speed up SPME method development and fiber selection.

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