The giant Detour Lake deposit is a Neoarchean orogenic Au ore body located in the northwestern Abitibi district within the Superior Province. The deposit is situated along the high strain Sunday Lake Deformation Zone (SLDZ) parallel to the broadly E-W trending Abitibi greenstone belt. The lower amphibolite facies assemblage (Act-Bt-Pl-Ep-Alm ±Cal ±Qz ±Ilm) suggests maximum temperatures reaching 550°C, exceeding conditions for pyrite plasticity, an important and ubiquitous Au-bearing phase that may ultimately represent the source for Au at orogenic style Au deposits. The metamorphic assemblage also obscures the relationship between Au and biotite, a visual indicator mineral within Au-rich ore zones. This work combines microstructural, geochemical and geochronological analyses to assess the influence of regional scale deformation and alteration on Au mineralization. EBSD and LA-ICP-MS analyses on pyrite reveal Au enrichment at microstructures supporting a syn- to post-peak metamorphic and deformation-assisted Au upgrading model. EMPA and 40Ar/39Ar analyses on biotite reveal one chemically homogeneous population, which yield variably reset ages that post-date regional metamorphism and Au mineralization.

Orientadores: Marcos Nogueira Eberlin, Maria Izabel Maretti Silveira Bueno / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-27T15:37:04Z (GMT). No. of bitstreams: 1 Schwab_NicolasVilczaki_D.pdf: 3814064 bytes, checksum: 830504748a20c22da41317192a1c7d9b (MD5) Previous issue date: 2015 / Resumo: O atual avanço na tecnologia em instrumentação analítica permite análises químicas cada vez mais rápidas e eficientes. Assim, o desenvolvimento de métodos que consistem em minimizar ou eliminar o preparo de amostra apresentam um grande diferencial em relação aos procedimentos tradicionais. Duas técnicas se destacam nesse sentido: a espectrometria de massas com ionização ambiente e a fluorescência de raios X por dispersão em energia. Com características distintas, essas técnicas abrangem um enorme campo de aplicações na ciência. Seguindo este conceito, esta tese de doutorado está dividida em três partes, que ilustram as diferentes aplicações utilizando uma das técnicas mencionadas. Primeiramente, foi relatada a produção e caracterização de superfícies funcionalizadas à base de silício poroso, como substrato para espectrometria de massas com ionização ambiente por dessorção via electrospray (DESI-MS). Os resultados encontrados mostraram que estas superfícies são excelentes alternativas como substrato para análises em DESI-MS, levando a baixos limites de detecção, eliminação de problemas referentes à contaminação cruzada e melhora na estabilidade do sinal analítico. O capítulo seguinte descreve o desenvolvimento de uma fonte portátil para ionização ambiente de moléculas por espectrometria de massas, que elimina a necessidade do uso de cilindros de gás e bombas injetoras. Sua eficiência foi comprovada por meio de análises de diversos compostos, gerando expectativas futuras para aplicações em campo, para resolução de casos analíticos conjuntamente com uso de equipamentos miniaturizados de espectrômetros de massas. Na parte final, foi demonstrado o uso da técnica de fluorescência de raios X na filatelia. Trata-se de uma técnica não destrutiva, onde, obteve-se o perfil elementar característico de diversas amostras de selos postais antigos como, por exemplo, os elementos relacionados à composição das tintas utilizadas na impressão. Como consequência, essa metodologia pode ser utilizada na discriminação em casos de falsificação de peças raras / Abstract: The advancement in analytical instrumentation allows today faster and more efficient chemical analysis. The development of new methods with regards to minimize or eliminate sample preparation steps has a great advantage over traditional procedures. Two techniques stand out in this concept: the ambient ionization mass spectrometry and energy dispersive X-ray fluorescence. With different characteristics, both techniques cover a huge range of applications in analytical chemistry. Following this idea, this thesis is divided into three parts that demonstrates some applications using the techniques mentioned earlier. The first chapter describes the production and characterization of functionalized porous silicon surfaces as substrates for desorption ionization electrospray mass spectrometry (DESI-MS). The results showed that specific surfaces provides an excellent alternative for spot analysis in DESI-MS, increasing detectability, eliminating cross-contamination problems and improving the analytical signal stability. The next chapter reports the development of a portable ambient ionization source for mass spectrometry, which eliminates the use of gas cylinders and injection pumps. Its efficiency was confirmed by analysis of several compounds leading to prospects for field applications; using for example with miniaturized mass spectrometers. Finally, the last chapter demonstrates the use of X-ray fluorescence in philately. The method developed is nondestructive and is a suitable technique to detect elements related with the composition of inks that are used to print stamps. For this reason, this is a powerful methodology to identify counterfeit samples of rare stamps mainly / Doutorado / Quimica Analitica / Doutor em Ciências

Orientador: Wilson de Figueiredo Jardim / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-27T18:04:13Z (GMT). No. of bitstreams: 1 Campestrini_Iolana_D.pdf: 2742870 bytes, checksum: 20a25893a0acbb614cce027eda2bef08 (MD5) Previous issue date: 2015 / Resumo: Este trabalho apresenta a determinação de sete subprodutos da cocaína (COC), incluindo a benzoilecgonina (BE), em amostras de urina de usuários da droga. Com os dados obtidos foi avaliada a incerteza no cálculo da razão entre a BE e o somatório dos demais metabólitos da COC, sendo que a razão média encontrada foi utilizada para inferir sobre o consumo de COC aplicando a epidemiologia do esgoto. Os resultados dessa razão apresentaram grande amplitude de valores e mostrou elevada influência sobre estimativa do consumo. Apresenta, também, a avaliação da eficiência de remoção (ER) para a COC e BE nas estações de tratamento de esgoto (ETE) Anhumas e Capivari e da qualidade de mananciais e de águas de abastecimento do estado de São Paulo. Os melhores índices de remoção foram observados para a ETE Capivari, os quais variaram entre 96 e 99%. Tanto nas amostras de mananciais como nas amostras de água de abastecimento, a BE foi determinada em maiores concentrações do que a COC. Nos rios Piracicaba, Capivari e Anhumas observaram-se os maiores níveis de BE, os quais variaram entre 300 e 1000 ng L-1. Nas amostras de água de abastecimento do rio Capivari e do rio Atibaia foram determinadas as maiores concentrações de BE, chegando a 650 ng L-1. Para a análise dessas amostras foi utilizada a extração em fase sólida (SPE) seguida da cromatografia líquida acoplada à espectrometria de massas sequencial (LC-MS/MS). No geral, o método apresentou exatidão superior a 70%, com coeficiente de variação menor do que 15% no nível de ng L-1 / Abstract: This work describes the determination of seven cocaine (COC) metabolites, including the major one benzoylecgonine (BE), in urine of cocaine users. These determinations allowed the calculation of the ratio between BE concentration and the sum of the other COC metabolites concentration, as well as allowed an assessment of the uncertainty involved in this ratio. The ratios were used to estimate cocaine consumption applying sewage epidemiology yielding high amplitude of values among the ratios calculated. The work also presents COC and BE removal efficiency (RE) in two wastewater treatment plant (WWTP), namely Anhumas and Capiravi, where the best RE were obtained for the Capivari WWTP, which varied between 96% and 99%. Also the assessment of water quality, for both surface and drinking waters of the State of São Paulo, Brazil, was evaluated. The metabolite BE occurred more frequently and at higher concentrations when compared to COC, considering the same samples. For surface water, the highest BE concentrations were found in the Piracicaba, Capivari and Anhumas rivers, and the results varied from 300 to 1000 ng L -1. For drinking waters, the highest BE concentration was found in waters from Capivari and Atibaia rivers, at 650 ng L-1. Solid phase extraction and the liquid chromatography tandem mass spectrometry (LC-MS/MS) were used for the determination of the compounds. In general, the method presented accuracy above 70% and relative standard deviation below 15%, at ng L -1 level / Doutorado / Quimica Analitica / Doutora em Ciências

Approximately 10 years ago, “bath salts” were popularized as legal alternatives to the psychostimulants cocaine and the amphetamines, circumventing legislation with packages marked, “not for human consumption.” These products contained synthetic cathinones including 3,4-methylenedioxypyrovalerone (MDPV), 4-methylmethcathinone (mephedrone), and 3,4-methylenedioxymethcathinone (methylone). The synthetic cathinones have similar pharmacology to controlled psychostimulants, increasing levels of dopamine (DA) in the synaptic cleft, while also exhibiting similar psychoactive effects such as increased energy and euphoria. Additionally, adverse effects of “bath salts” are similar to controlled psychostimulants, such as chest pain, shortness of breath, and hallucinations. Most preclinical investigations have only assessed the effects of these synthetic cathinones independently; however, case reports and DEA studies indicate that “bath salts” contain mixtures of these substances. Therefore, in a recent study by our laboratory, we examined effects of individual versus combined exposure to MDPV, mephedrone, and methylone. Interestingly, an enhanced effect on the levels of DA in a number of brain regions was observed, as well as significant alterations in locomotor activity following co-exposure to the cathinones. Here, we examine if the enhanced effects of the drug combination are due to pharmacokinetic (PK) interactions. Many of the same cytochrome isoenzymes metabolize each of these 3 drugs; thus, it is probable that the drugs’ PK would differ when administered individually as compared to in combination. We hypothesized that combined exposure to MDPV, mephedrone, and methylone would result in increased total drug concentrations when compared to individual administration. Briefly, adolescent male Swiss-Webster mice were injected intraperitoneally with either 10 mg/kg MDPV, 10 mg/kg mephedrone, 10 mg/kg methylone, or 10 mg/kg combined MDPV, mephedrone, and methylone. Following injection, brains and plasma were collected at the following time points: 1, 10, 15, 30, 60, and 120 minutes. Drugs were extracted via solid-phase extraction, and concentrations were determined using a previously published high pressure-liquid chromatography tandem mass spectrometry method. All drugs quickly crossed the blood-brain barrier and entered the brain. PK data for methylone and mephedrone was consistent with our hypothesis. For methylone, the maximal concentration (Cmax) and the total drug exposure (as represented by the area under the curve (AUC)) were significantly higher when combined with mephedrone and MDPV in both matrices. For mephedrone, the Cmax was unchanged, but AUC in brain was increased when combined with the other two drugs. However, interestingly, for MDPV, the Cmax was unchanged, yet the AUC in brain was higher when MDPV was administered individually. These data provide insight into the consequences of co-exposure to synthetic cathinones in popular “bath salt” products.

La pollution de l'eau est l'une des menaces écologiques les plus sérieuses au niveau des pays industrialisés et des pays en cours de développement. Les polluants sont rejetés directement ou indirectement dans les ressources en eau telles que les rivières, les lacs, les aquifères et les eaux côtières sans prétraitement approprié ; transformant ainsi nos systèmes aquatiques en un dépotoir fortement pollué par des contaminants toxiques et persistants tels que les contaminants organiques. Les hydrocarbures Aromatiques Polycycliques (HAPs) et les pesticides sont parmi les polluants organiques les plus périlleux que l'on retrouve à l’état de traces dans les milieux aquatiques. Pour cette raison, leur analyse nécessite une procédure d'extraction suivie de méthodes analytiques très sensibles et spécifiques. Dans ce contexte, le travail de cette thèse a porté en premier lieu sur le développement de deux méthodes analytiques distinctes. La première a été consacrée à l'extraction et à l'analyse des 16 HAPs prioritaires classés par l’agence de protection de l’environnement (EPA) dans. Dans cette méthode, nous nous sommes concentrés sur l'optimisation et la validation des paramètres de la spectrométrie de masse en tandem (MS / MS) afin de réduire le bruit de fond. La deuxième méthode était dédiée à l'analyse de quarante-huit pesticides dans l'eau. Dans cette méthode, les paramètres de la micro-extraction sur phase solide (SPME) et de la chromatographie en phase gazeuse couplée à la spectrométrie de masse en tandem GC-MS / MS ont été optimisés et validés. Les deux méthodes se sont révélées très sensibles, précises et sélectives pour l'analyse de ces deux familles de contaminants organiques. La deuxième partie de cette thèse était dirigée sur l'évaluation de la qualité de l'eau le long du bassin versant de la rivière Abou Ali en termes de contamination par les HAPs et les pesticides. Pour ce faire, les méthodes précédemment développées et optimisées ont été utilisées pour l'analyse. Les résultats obtenus pour les échantillons d'eau de surface ont révélés une contamination considérable par les HAPs et les pesticides à différents endroits le long du bassin versant. Cependant, pour les échantillons d'eau souterraine, aucune ou très faible concentration de HAPs et de pesticides n'a été détectée. Cette étude est la première de son genre concernant l'analyse des HAPs et des pesticides dans la zone étudiée. Elle donne un aperçu global de la qualité de l'eau le long du bassin versant et insiste sur l'importance de réaliser des mesures continues afin d'avoir une base de données complète non seulement pour la zone d'étude ou le Liban nord mais pour toutes les régions du territoire libanais. / Water pollution is one of the most thoughtful ecological threat imperiling the industrial and developing countries. Pollutants are released directly or indirectly into water resources such as rivers, lakes, aquifers and coastline waters without any suitable pre-treatment; thus transforming our aquatic systems into a dumpsite heavily polluted with toxic and persistent contaminants such as organic contaminants. Polycyclic Aromatics Hydrocarbons (PAHs) and pesticides are among the most perilous organic pollutants that are found in trace levels in aquatic environments. For this reason, their analysis requires an extraction procedure followed by highly sensitive and specific analytical methods. In this context, this work has focused, as a first step, on the development of two separate analytical methods. The first one was dedicated to the extraction and analysis of the 16 priority PAHs in water, listed by the environmental protection agency (EPA). In this method, we have focused on the optimization and validation of tandem mass spectrometry (MS/MS) parameters in order to reduce background noise. The second method was for the analysis of 48 pesticides in water where the solid-phase micro-extraction (SPME) and gas chromatography tandem mass-spectrometry GC-MS/MS parameters were optimized and validated. Both methods were found to be highly sensitive, precise and selective for the analysis of these two families of organic contaminants. As for the second part of this work, the assessment of the water quality along the watershed of Abou Ali River, in terms of its contamination by PAHs and pesticides, was performed. For this aim, the previously developed and optimized methods were used for the analysis. The results obtained for surface water samples revealed a considerable contamination by PAHs and pesticides in different locations along the watershed. However, for groundwater samples no or very low concentrations of PAHs and pesticides were detected. This study is the first of its kind concerning the analysis of PAHs and pesticides in the studied area. It provided an overview of the water quality along the watershed and stressed on the importance to do ongoing measurements in order to have a complete database not only for the studied area or the North of Lebanon, but for all the regions in the Lebanese territory.

The work described in this dissertation is divided into three sections. In the first section three surface modifications are used to produce MALDI targets having reduced surface-protein binding affinity with a goal of increasing peptide/protein MALDI ion signals and lowering the limits of detection (LODs) for proteins and peptides. The second section discusses a bioselective MALDI target, produced via radio frequency (rf) plasma deposited ethylenediamine (EDA), for on-target separation of complex protein mixtures. The third section develops a new approach for characterization of rf plasma-deposited bulk polymers by using MALDI MS. Previous studies in our group have shown that the analyte signal in a MALDI MS experiment is strongly influenced by the binding interactions between the target surface and the analyte. Specifically, the analyte signal increases with decreasing surface-analyte binding affinity, which has been attributed to more unbound analyte being available for incorporation within the MALDI matrix. In the presented studies MALDI targets are modified with polyethylene glycol (PEG)-like structures via chemical grafting of PEG onto polyurethane (PU) film and rf plasma polymerization of ethylene oxide vinyl ether (EO2) and tetraglyme. It is shown that there are enhancements in the protein MALDI ion signals on these modified targets and that the LOD for target proteins is decreased by a factor of 2-10 in comparison with the conventional stainless steel MALDI target. On-probe affinity capture (OPAC) MALDI MS, developed in our group, has shown that functional group modified MALDI targets can be used to rapidly and selectively isolate target analytes from complex samples. For applications involving analysis of complex peptide/protein mixtures, fractionation of the mixture on the basis of component pI can reduce MALDI ion suppression effects leading to efficient ionization of larger numbers of mixture components. In the present studies a MALDI target is modified by rf plasma deposition of polymerized EDA to yield an OPAC target suitable for capture of proteins with low pI (expected to be negatively charged at neutral pH). In subsequent MALDI MS analyses of both control and biological mixtures after fractionation on the OPAC target it is observed that a significant number of additional peptide/protein ion signals are detected. The results of these studies, along with studies of the effects of the density of the primary amine functionality on the bio-selective MALDI ion signals, are presented. The complex nature of the polymer films resulting from plasma polymerization makes it very difficult to characterize their molecular structures. The presented study is the first to use MALDI MS for characterization of rf plasma-deposited bulk polymers and for investigation of the rf plasma polymerization process. It is shown that the mass spectra of the soluble fraction of allyl alcohol, EO2 and ethylene glycol butyl vinyl ether -plasma polymers contain clear polymer series. Furthermore, it is found that the peaks of the EO2-plasma polymer series shift to higher molecular weight distribution with decreasing plasma duty cycle. In contrast to predictions based on conventional radical polymerization, the mass spectra of all three plasma polymers exhibit the same repeat unit of 44 Da, for which the most likely structure would be -(CH2CH2O)-.

No description available.

A bioluminescência desperta o interesse humano há muitos séculos. Presente em quatro dos sete reinos taxonômicos, Monera, Chromista, Animalia e Fungi, cada um com mecanismos muito diferentes. Pode-se dizer que o estudo químico da bioluminescência começou com os experimentos de Dubois no século XIX, que cunhou os termos luciferina e luciferase, termos genéricos para o substrato e enzima envolvidos na reação, respectivamente. No caso específico de fungos, o envolvimento de enzimas foi debatido por quase cinco décadas, após a proposta enzimática de Airth e Foerster na década de 1960 e a não enzimática por Shimomura, em 1989. Somente em 2009 a hipótese de Airth e Foerster foi confirmada pelo nosso grupo, seguido da identificação da luciferina fúngica e o envolvimento de hispidina, como molécula precursora, em 2015 pelo grupo de Yampolsky. Para conseguir elucidar mecanismos químicos, a técnica de espectrometria de massas pode ser empregada para a identificação estrutural de reagentes e intermediários destas e de outras reações orgânicas. Após a confirmação do envolvimento de hispidina na bioluminescência de fungos, utilizou-se a técnica de cromatografia líquida acoplada a espectrometria de massas para identificar a presença de hispidina, seus derivados e intermediários precursores, em fungos e em algumas plantas. / Bioluminescence arises human interest for centuries. Occurring in four of seven taxonomical Kingdoms, Monera, Chromista, Animalia and Fungi, each of them with completely different mechanisms. The chemical study of bioluminescence starts in XIX century with Dubois, who coined the terms luciferin and luciferase, generic terms for substrate and enzyme involved in the bioluminescent reaction, respectively. In the specific case of fungi, enzyme involvement has been debated for almost five decades, after the enzymatic proposal by Airth and Foerster, during the 1960 decade, and the non-enzymatic proposal by Shimomura in 1989. It was only in 2009 when the proposal by Airth and Foerster was confirmed by our group, followed by the identification of the fungal luciferin and the involvement of hispidin, as the precursor molecule, in 2015 by Yampolskys group. To elucidate the chemical mechanisms, mass spectrometry can be employed to structural identification of reagents and intermediates on these and other organic reactions. After the confirmation of hispidin involvement in fungi bioluminescence, liquid chromatography coupled with mass spectrometry was uses do identify the presence of hispidin, its derivatives and precursor intermediates in fungi and selected plants.

A ifosfamida é um pró-fármaco que apresenta um átomo de fósforo quiral, disponível na clínica como mistura racêmica dos enantiômeros(+)-(R)-ifosfamida e (-)-(S)-ifosfamida para a utilização na quimioterapia. O objetivo do presente estudo foi o de avaliar a disposição cinética dos enantiômeros da ifosfamida em plasma de pacientes portadoras de câncer de colo do útero. As pacientes investigadas (n=6) receberam 2,5 g/m2 de ifosfamida racêmica administrada como infusão de 12 horas, sendo coletadas amostras de sangue imediatamente antes da administração e em 6, 10, 11, 12, 13, 14, 16, 18, 20 e 22 horas após a administração do fármaco. Os enantiômeros da ifosfamida foram quantificados por LC-MS/MS, sendo separados na coluna OD-R em aproximadamente 14 min empregando como fase móvel mistura de acetonitrila e água (20:80) adicionada de 0,2% de ácido fórmico. O método é linear no intervalo de 1-100 ?g de cada enantiômero/mL de plasma a partir de extrações de alíquotas de 25 ?L de plasma, compatíveis com a aplicação em farmacocinética de infusão de curta duração da ifosfamida em pacientes com câncer de colo do útero.A disposição cinética da ifosfamidaéenantiosseletiva, com observação de maiores valores de AUC (437,31 vs349,18 h.?g/mL) e menores valores de clearance(4,17 vs5,22 L/h) para o enantiômero(+)-(R)-ifosfamida. / The prodrugifosfamide has a chiral phosphorus atom, and is available clinically as a racemic mixture of the enantiomers (+)-(R)-ifosfamide and (-)-(S)-ifosfamide for use in chemotherapy. The aim of this study was to evaluate the kinetic disposition of the enantiomers of ifosfamide in plasma of patients with cancer of the cervix. The investigated patients (n = 6) received 2.5 g/m2 of racemic ifosfamide administered as infusion of 12 hours and blood samples were collected immediately before administration and at 6, 10, 11, 12, 13, 14, 16, 18, 20 and 22 hours after drug administration. The enantiomers of ifosfamide were quantified by LC-MS/MS and were separated in an OD-R column in about 14 min using as mobile phase a mixture of acetonitrile and water (20:80) plus 0.2% of formic acid. The method is linear within the range of 1-100 mg of each enantiomer/mL of plasma from extractions of 25 mL aliquots of plasma, suitable for the application in pharmacokinetics of short duration infusion of ifosfamide in patients with cervical cancer. The kineticdisposition of ifosfamide is enantioselective, with observation of higher values of AUC (437.31 vs 349.18 h.?g/mL) and lower values of clearance (4.17 vs 5.22 L/h) for the enantiomer (+)-(R)-ifosfamide.

A bioluminescência desperta o interesse humano há muitos séculos. Presente em quatro dos sete reinos taxonômicos, Monera, Chromista, Animalia e Fungi, cada um com mecanismos muito diferentes. Pode-se dizer que o estudo químico da bioluminescência começou com os experimentos de Dubois no século XIX, que cunhou os termos luciferina e luciferase, termos genéricos para o substrato e enzima envolvidos na reação, respectivamente. No caso específico de fungos, o envolvimento de enzimas foi debatido por quase cinco décadas, após a proposta enzimática de Airth e Foerster na década de 1960 e a não enzimática por Shimomura, em 1989. Somente em 2009 a hipótese de Airth e Foerster foi confirmada pelo nosso grupo, seguido da identificação da luciferina fúngica e o envolvimento de hispidina, como molécula precursora, em 2015 pelo grupo de Yampolsky. Para conseguir elucidar mecanismos químicos, a técnica de espectrometria de massas pode ser empregada para a identificação estrutural de reagentes e intermediários destas e de outras reações orgânicas. Após a confirmação do envolvimento de hispidina na bioluminescência de fungos, utilizou-se a técnica de cromatografia líquida acoplada a espectrometria de massas para identificar a presença de hispidina, seus derivados e intermediários precursores, em fungos e em algumas plantas. / Bioluminescence arises human interest for centuries. Occurring in four of seven taxonomical Kingdoms, Monera, Chromista, Animalia and Fungi, each of them with completely different mechanisms. The chemical study of bioluminescence starts in XIX century with Dubois, who coined the terms luciferin and luciferase, generic terms for substrate and enzyme involved in the bioluminescent reaction, respectively. In the specific case of fungi, enzyme involvement has been debated for almost five decades, after the enzymatic proposal by Airth and Foerster, during the 1960 decade, and the non-enzymatic proposal by Shimomura in 1989. It was only in 2009 when the proposal by Airth and Foerster was confirmed by our group, followed by the identification of the fungal luciferin and the involvement of hispidin, as the precursor molecule, in 2015 by Yampolskys group. To elucidate the chemical mechanisms, mass spectrometry can be employed to structural identification of reagents and intermediates on these and other organic reactions. After the confirmation of hispidin involvement in fungi bioluminescence, liquid chromatography coupled with mass spectrometry was uses do identify the presence of hispidin, its derivatives and precursor intermediates in fungi and selected plants.