Dissertations / Theses: 'NanoLC FT MS/MS'

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Camperi, Julien. "Développement de méthodes séparatives pour la caractérisation d’une glycoprotéine intacte : application à l’hormone chorionique gonadotrophine humaine." Thesis, Paris Sciences et Lettres (ComUE), 2018. http://www.theses.fr/2018PSLET018.

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La glycosylation est la forme la plus courante de modification post-traductionnelle (PTM) des protéines humaines, puisque plus de 70% d’entre elles sont glycosylées. Celle-ci régule de nombreuses propriétés biologiques comme leur stabilité, leur demi-vie et leur activité. Néanmoins, les protéines peuvent également présenter d'autres types de PTM, ce qui peut conduire pour une protéine donnée à un très grand nombre d'isoformes variant par leur masse, leurs propriétés biologiques et physico-chimiques et leur concentration dans les échantillons biologiques. Ainsi, caractériser une glycoprotéine comporte de nombreux défis et nécessite la mise en œuvre de méthodes séparatives très performantes et de détection très sensibles et informatives.La gonadotrophine chorionique humaine (hCG) est l’hormone spécifique de la grossesse humaine. Elle est essentielle au développement du placenta et du fœtus. Elle est composée de deux sous-unités hCGα et hCGβ qui sont fortement glycosylées (4 sites de N-glycosylation et 4 sites d’O-glycosylation). Récemment, des travaux ont montré une corrélation entre sa glycosylation et une bonne implantation du fœtus. Une caractérisation des ces glycoformes s’avère donc nécessaire.Par conséquent, de nouvelles méthodes en LC/CE-MS ont été développées pour la caractérisation de la hCG à l’échelle intacte en utilisant deux médicaments à base de hCG ayant des glycosylations différentes. Alors que la méthode en CZE-MS (TQ) a permis de différencier les profils des glycoformes de la sous-unité hCGα des deux médicaments, la complémentarité des méthodes RP- et HILIC-MS (qTOF) a conduit à leur identification.Pour limiter les erreurs potentielles d’identification dues au chevauchement des profils isotopiques, le profil de chaque isoforme a été résolu par FT-ICR MS. Dans ce but, une séparation au format nanoLC en mode RP a été développée, améliorant ainsi la sensibilité de la méthode d’un facteur 500 par rapport au format conventionnel. Cette méthode a permis de confirmer l’identification des glycoformes de la sous-unité hCGα. D’autre part, il a été possible d’obtenir des profils différents de glycosylation de la sous-unité hCGβ en favorisant leur ionisation par réduction de la hCG. Enfin, un traitement à la PNGase a conduit à l’élimination des N-glycanes pour l’obtention des profils d’O-glycosylation de la sous-unité hCGβ
Glycosylation is the most common form of post-translational modifications (PTMs) of human proteins, since more than 70% are glycosylated. It regulates numerous biological properties including their stability, half-life, and activity. Nevertheless, proteins can also exhibit other types of PTMs that lead to a very large number of isoforms, varying in mass, properties and concentration in the biological samples. Therefore, the characterization of a glycoprotein is highly challenging and requires the use of powerful separation techniques and sensitive and informative detection modes.The human chorionic gonadotropin (hCG) is the hormone specific to human pregnancy. It is essential for the development of placenta and fetus. It is based on two heavily glycosylated subunits, hCGα and hCGβ, having 8 glycosylation sites (4 N- and 4 O-glycosylation sites). Some recent studies demonstrated that here is a correlation between the hCG glycosylation state and the fetus implantation. This is why the characterization of the hCG glycoformes is needed.Therefore, new LC/CE-MS methods were developed for the characterisation of hCG at the intact level using two hCG-based drugs having different glycosylation profiles. While the CZE-MS (TQ) method showed its potential for glycosylation fingerprinting, the complementarity of LC-(qTOF) MS methods in RP and HILIC modes allowed the identification of the glycoforms of the hCGα subunit.To limit the identification errors due to the overlapping of isotopic distribution patterns, the profile of each isoform was resolved by FT-ICR MS. For this purpose, a nanoLC separation in RP mode was developed, thus improving the sensitivity of the method by a factor 500 compared to the conventional format. This method allowed the confirmation of the identification of hCGα glycoforms. Then, it was possible to obtain different glycosylation patterns of the hCGβ by promoting its ionization after hCG reduction. Then, a PNGase treatment was carried out to remove the N-glycans in order to obtain the O-glycoprofiles of hCGβ isoforms

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Emmanuel, Alexandra. "Mise en place d’une approche protéomique en vue d’une application au diagnostic d’infections parasitaires congénitales." Electronic Thesis or Diss., Sorbonne Paris Cité, 2017. http://www.theses.fr/2017USPCB137.

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Au cours des deux dernières décennies, la spectrométrie de masse (MS) est devenue un outil incontournable dans la caractérisation des protéines comme les IgG. Ces anticorps assurent la protection de l'organisme contre les antigènes, qu'ils reconnaissent grâce aux domaines variables de leurs chaînes lourdes et légères. Des séquences polymorphes existent également au niveau des domaines constants CH2 et CH3 du fragment Fc, impliquant quelques acides aminés, qui définissent ainsi 34 allèles protéiques IGHG des 4 sous-classes d'IgG. Des relations sont établies entre certains de ces polymorphismes et la fonctionnalité de la réponse anticorps. La caractérisation du polymorphisme allélique des IgG par la MS est fréquemment effectuée par la stratégie bottom-up. Cette approche analytique repose sur l'analyse des protéines digérées par des endoprotéases classiques (comme la trypsine) générant des peptides protéolytiques (~30 acides aminés). Nous avons donc utilisé cette méthode combinée à des approches de biologie moléculaire pour étudier ce polymorphisme. Cependant la présence, pour un même individu, de plusieurs allèles d'homologie très forte limite la caractérisation spécifique des séquences de Fc. Dans ce contexte, nous avons développé une approche middle-down permettant d'analyser de grands fragments peptidiques (~ 211 acides aminés). IdeS est une endoprotéase spécifique des IgG qui génère spécifiquement deux fragments : les fragments Fc/2 et F(ab')2. Ces fragments sont alors étudiés par nanoLC-MS/MS à très haute résolution (140000 à m/z 200). La fragmentation des ions précurseurs a été réalisée en mode HCD (higher-energy collisional dissociation). Les données obtenues ont été traitées pour recherche dans les banques de données et les résultats ont été validés manuellement. Malgré la faible performance des logiciels disponibles à ce jour pour automatiser ce traitement, notre approche montre qu'il est possible de discriminer plusieurs allèles IGHG des différentes IgG. Au vu de la forte homologie de séquence il est important d'optimiser la couverture de séquence car certains allèles ne diffèrent que d'un résidu sur les 211 acides aminés séquencés. Cette preuve de concept des capacités d'une analyse middle-down pour identifier les différents Fc/2 pourrait à l'avenir être utilisée comme outil diagnostic pour la caractérisation des polymorphismes des Fc/2 dans un contexte de suspicion d'infections parasitaires congénitales
Over the past two decades, mass spectrometry (MS) has become an essential tool in the characterization of proteins such as IgG. These antibodies protect the organism against antigens, which they recognize through the variable domains of their heavy and light chains. Polymorphic sequences also exist at the constant domains CH2 and CH3 of the Fc fragment, involving a few amino acids, which thus define 34 IGHG protein alleles of the 4 IgG subclasses. Relationships are established between some of these polymorphisms and the functionality of the antibody response. The characterization of allelic polymorphism of IgG by MS is frequently carried out by the bottom-up strategy. This analytical approach relies on the analysis of proteins digested by conventional endoproteases (such as trypsin) generating proteolytic peptides (~ 30 amino acids). We have therefore used this method combined with molecular biology approaches to study this polymorphism. However, the presence, for the same individual, of several alleles of very strong homology limits the specific characterization of the sequences of Fc. In this context, we developed a middle-down approach to analyze large peptide fragments (~ 211 amino acids). IdeS is an IgG-specific endoprotease that specifically generates two fragments: the Fc/2 and F (ab')2 fragments. These fragments are then studied by nanoLC-MS/MS at very high resolution (140000 at m/z 200). The fragmentation of the precursor ions was carried out in HCD (higher-energy collisional dissociation) mode. The data obtained were processed and searched in the databases and the results were validated manually. Despite the poor performance of the software available to date due to limited automation, our approach shows that it is possible to discriminate several IGHG alleles from different IgGs. In view of the high sequence homology it is important to optimize the sequence coverage because some alleles differ only by one residue over the 211 amino acids sequenced. This proof of concept of the capabilities of a middle-down analysis to identify different Fc/2 could be used in the future as a diagnostic tool for the characterization of Fc /2 polymorphisms in a context of suspicion of congenital parasitic infections

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Danne-Rasche, Niklas [Verfasser], and Oliver [Akademischer Betreuer] Schmitz. "Development of a nanoLC-MS system for global lipidomics / Niklas Danne-Rasche ; Betreuer: Oliver Schmitz." Duisburg, 2021. http://d-nb.info/1232176036/34.

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Mitchell, Joshua Merritt. "Computational Tools for the Untargeted Assignment of FT-MS Metabolomics Datasets." UKnowledge, 2019. https://uknowledge.uky.edu/biochem_etds/42.

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Metabolomics is the study of metabolomes, the sets of metabolites observed in living systems. Metabolism interconverts these metabolites to provide the molecules and energy necessary for life processes. Many disease processes, including cancer, have a significant metabolic component that manifests as differences in what metabolites are present and in what quantities they are produced and utilized. Thus, using metabolomics, differences between metabolomes in disease and non-disease states can be detected and these differences improve our understanding of disease processes at the molecular level. Despite the potential benefits of metabolomics, the comprehensive investigation of metabolomes remains difficult. A popular analytical technique for metabolomics is mass spectrometry. Advances in Fourier transform mass spectrometry (FT-MS) instrumentation have yielded simultaneous improvements in mass resolution, mass accuracy, and detection sensitivity. In the metabolomics field, these advantages permit more complicated, but more informative experimental designs such as the use of multiple isotope-labeled precursors in stable isotope-resolved metabolomics (SIRM) experiments. However, despite these potential applications, several outstanding problems hamper the use of FT-MS for metabolomics studies. First, artifacts and data quality problems in FT-MS spectra can confound downstream data analyses, confuse machine learning models, and complicate the robust detection and assignment of metabolite features. Second, the assignment of observed spectral features to metabolites remains difficult. Existing targeted approaches for assignment often employ databases of known metabolites; however, metabolite databases are incomplete, thus limiting or biasing assignment results. Additionally, FT-MS provides limited structural information for observed metabolites, which complicates the determination of metabolite class (e.g. lipid, sugar, etc. ) for observed metabolite spectral features, a necessary step for many metabolomics experiments. To address these problems, a set of tools were developed. The first tool identifies artifacts with high peak density observed in many FT-MS spectra and removes them safely. Using this tool, two previously unreported types of high peak density artifact were identified in FT-MS spectra: fuzzy sites and partial ringing. Fuzzy sites were particularly problematic as they confused and reduced the accuracy of machine learning models trained on datasets containing these artifacts. Second, a tool called SMIRFE was developed to assign isotope-resolved molecular formulas to observed spectral features in an untargeted manner without a database of expected metabolites. This new untargeted method was validated on a gold-standard dataset containing both unlabeled and 15N-labeled compounds and was able to identify 18 of 18 expected spectral features. Third, a collection of machine learning models was constructed to predict if a molecular formula corresponds to one or more lipid categories. These models accurately predict the correct one of eight lipid categories on our training dataset of known lipid and non-lipid molecular formulas with precisions and accuracies over 90% for most categories. These models were used to predict lipid categories for untargeted SMIRFE-derived assignments in a non-small cell lung cancer dataset. Subsequent differential abundance analysis revealed a sub-population of non-small cell lung cancer samples with a significantly increased abundance in sterol lipids. This finding implies a possible therapeutic role of statins in the treatment and/or prevention of non-small cell lung cancer. Collectively these tools represent a pipeline for FT-MS metabolomics datasets that is compatible with isotope labeling experiments. With these tools, more robust and untargeted metabolic analyses of disease will be possible.

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Vaz, Boniek Gontijo. "Petroleômica por FT-ICR MS = desvendando a composição de polares do petróleo e derivados." [s.n.], 2011. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248707.

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Orientador: Marcos Nogueira Eberlin
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: A ionização por eletrospray (ESI) acoplada com a espectrometria de massas de ressonância ciclotrônica de íons por transformada de Fourrier (FT-ICR MS) permite a detecção de milhares de compostos polares (N, S e O) no petróleo e seus derivados, sem separação cromatográfica. ¿Petroleômica¿ é, portanto, a caracterização do petróleo a nível molecular. Neste trabalho, petróleos de diferentes níveis de evolução térmica, amostras de diesel obtidas por processos diferentes (hidrotratamento e oxitratamento) e cortes de destilação obtidos da destilação molecular de resíduo de petróleo foram analisados usando esta técnica. A primeira parte do trabalho consistiu na análise de petróleos com diferentes níveis de evolução térmica. Com o aumento do estresse térmico, observou-se um aumento da condensação, da aromatização de estruturas cíclicas polares e uma diminuição do número de carbono das classes de compostos identificadas. A intensidade relativa dos compostos pirrólicos foi usada para agrupar os óleos de mesmo nível de evolução térmica usando Análise dos Componentes Principais (PCA), que mostrou bastante eficiente. Na segunda parte, a análise de amostras de diesel obtidas por condições operacionais diferentes (temperatura, pressão e velocidade espacial) do hidrotratamento e pelo processo de oxitratamento, mostrou a produção, respectivamente, de espécies de baixo valores de DBE (do inglês Double Bond Equivalent), devido a hidrogenação dos anéis aromáticos presentes nos compostos polares, e uma variedade de classes contendo mais que um heteroatômo, como Ox ,NOx and SOx, devido a oxidação química dos hidrocarbonetos e compostos polares. A última parte consistiu na análise dos cortes de destilação. Evidenciaram-se com a caracterização de cada corte de destilação as tendências composicionais com aumento da temperatura de destilação. O peso molecular, aromaticidade, o conteúdo de heteroátomos e a distribuição do número de carbono aumentaram proporcionalmente a temperatura de destilação. Os resultados mostraram que é possível a partir dos milhares de compostos, identificados rotineiramente por FT-ICR MS, predizer as propriedades do petróleo e seus derivados, como também na otimização de processos como aqueles que reduzem o nível dos compostos NOS
Abstract: Electrospray ionization (ESI) coupled with Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) allows the direct detection of thousands of polar compounds (N, S and O) in petroleum and its derivatives, without chromatographic separation. ''Petroleomics¿¿ is therefore the characterization of petroleum at the molecular level. In this work, oils from different levels of thermal maturity, diesel fuel obtained by different processes (hydrotreatment and oxitreatment) and distillate cuts obtained from molecular distillation of petroleum residue were analyzed using this technique. The first part of this study consisted in the analysis of oils of different levels of thermal maturity. With increasing thermal stress, condensation and aromatization of the polar cores increase, and the number of alkyl carbons decreases. The relative intensity of the pyrrolic compounds were used for grouping the oils with same level of thermal maturity by Principal Analysis Components (PCA), that shown to be quite efficient. In a second step, the analysis of different diesel fuel oil samples, obtained from different operational conditions (temperature, pressure and liquid hourly space velocity) of hydrotreatment and by oxitreatment process, showed the production, respectively, of lower DBE (Double Bond Equivalent) species, due the hydrogenation of the aromatic rings present in the polar compounds, and a variety of classes containing more than one heteroatom, such as Ox ,NOx and SOx, due the chemical oxidation of hydrocarbons and heteroatom compounds present in these fuel. The last stage consisted in the analysis of distillate cuts. Each distillate cut was characterized to mark compositional trends with increased distillation temperature. The molecular weight, aromaticity, heteroatom content and carbon number distribution increase proportionately with the temperature. The results show that it is possible from the thousands compounds, identified routinely by FTICR MS analysis, predict the properties of petroleum and its derivatives, as well help improve processes such that used for reduce the level of NSO compounds
Doutorado
Quimica Organica
Doutor em Ciências

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Boutegrabet, Lemia. "Approche métabolomique dans l'analyse de l'évolution oxydative des vins en spectrométrie de masse à très haute résolution." Thesis, Dijon, 2012. http://www.theses.fr/2012DIJOS025.

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Tout au long du procédé d’élaboration d’un vin, des réactions d’oxydation peuvent se produire y compris au cours du vieillissement en bouteilles. Depuis quelques années, la profession viti-vinicole est confrontée au problème de l’oxydation prématurée des vins blancs.. A ce jour, peu d’études ont pu apporter des explications d’ordre chimique à ce phénomène, et les mécanismes réactionnels intervenant restent peu connus.L’objectif de ce travail de thèse est d’apporter, au travers d’une analyse moléculaire non ciblée en spectrométrie de masse à transformée de Fourier et à résonance cyclotronique des ions (FT-ICR-MS) couplée à une étude chimiométrique, des réponses originales aux questions posées par la problématique actuelle d’oxydation prématurée des vins blancs. Nous avons montré suite à l’étude d’une série de vins oxydés prématurément non seulement la grande diversité chimique des vins, mais aussi la présence d’un ensemble de masses typiques associées à ce phénomène. Pour une meilleure compréhension de l’origine de cette problématique, nous avons considéré deux autres types d’oxydation : une oxydation relative exclusivement à un apport contrôlé en oxygène et une autre relative à l'évolution naturelle de vins en bouteilles. Cette dernière consiste en le suivi de l'évolution des espaces chimiques de séries verticales de vins blancs et rouges en fonction du temps. Sur la série verticale des vins blancs allant de 1979 à 2006, une charnière à l’année 1990 a été observée avec des groupes de masses typiques de chacun des vins jeunes (1979-1990) et des vieux vins (1991-2006).La comparaison entre les espaces chimiques discriminants chacun de ces trois types d’oxydation ne révèle la présence que de trois masses en commun, ce qui appuie l'hypothèse de causes multiparamétriques à l’oxydation prématurée des vins blancs, qui ne serait donc pas un phénomène du exclusivement à une exposition non contrôlée à l'oxygène.Des essais d’élucidation structurale en FT-ICR-MS/MS des masses discriminantes des vins oxydés et de la série verticale ont été effectués et des schémas de fragmentation pour certaines masses sont proposés
During winemaking processes, many oxidation reactions may occur especially during the aging period. Recently, white wines are characterized by a problem of premature oxidation for which few studies have provided chemical explanation. To date, the involved mechanisms in this phenomenon remain poorly understood.The aim of this thesis project is to provide, through an untargeted molecular analysis using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS) coupled to chemometric analysis, original clue to understand the premature oxidation of white wines. Based on the study of a series of premature oxidized white wines, we were able to elucidate the high complexity and the chemical diversity of wine, and got out typical masses characterizing the oxidation state. In order to better understand the origin of this phenomenon, we considered two alternative possibilities of oxidation: the first one induced by oxygen, and the second through a natural evolution of wines in bottles. The latter included the monitoring of the chemical evolution of white and red wines as a function of time. A very interesting result was obtained on the vertical series of white wines from 1979 to 2006, where two groups were separated at the 1990 vintage to provide a group of old wines (1979-1990) and a group of new wines (1991-2006). Typical discriminant masses were found for each group.A comparison between the chemical spaces discriminating each of the three types of oxidation (premature oxidation, oxidation with oxygen and natural evolution of wine in bottle) revealed very few common masses that may indicate that the phenomenon of premature oxidation is indeed influenced by multiple factors.Finally, a structural elucidation of the typical masses of the groups of oxidized and aged wines were established using FT-ICR-MS/MS. Possible fragmentations schemes of some of these masses were proposed

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Brunel, Benoît. "Détermination des interactions microscopiques entre les actinides and les substances humiques." Thesis, Paris 11, 2015. http://www.theses.fr/2015PA112024/document.

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Détermination des interactions microscopiques entre les actinides et les substances humiques présentes dans l’environnementUne quantité pondérable de plutonium a été introduite dans l’environnement lors d’essais nucléaires ou d’accidents civils. Les zones contaminées, nécessitant une surveillance particulière, sont devenues des lieux d’études très intéressants pour comprendre le comportement du plutonium dans l’environnement. Jusqu’à peu de temps encore, il était admis que le plutonium introduit dans les sols était relativement immobile en raison de sa propension à se sorber fortement sur les roches et de sa faible solubilité dans l’eau. Cependant, des études menées sur des zones contaminées montrent que les substances humiques, omniprésentes dans l’environnement, peuvent influencer la spéciation d’un métal et donc sa migration. C’est pourquoi, il est indispensable de connaître l’influence des substances humiques sur la spéciation du plutonium pour comprendre le transport de celui-ci dans un milieu naturel. Toutefois, en raison de la nature complexe et hétérogène de la matière organique naturelle, il est difficile de décrire de façon microscopique les interactions entre substances humiques et le plutonium. En effet, les substances humiques forment un mélange hétérogène de supra-molécules polydispersées produites par des réactions chimiques ou biochimiques durant la transformation naturelle de matière organique animale, végétale ou microbienne.Le but de ces travaux est d’évaluer à l’échelle de moléculaire les phénomènes de complexation des actinides par la matière organique naturelle. Ces recherches s’organisent autour de deux axes : la caractérisation de dizaines de milliers de molécules dans chaque échantillon de substances humiques naturelles et la détermination des molécules responsables de la vectorisation des actinides dans l’environnement.La mise au point d'une méthodologie a permis de mettre en évidence, pour la première fois, quelques molécules responsables de la complexation des actinides dans des échantillons de matière organique naturelle. Les résultats obtenus montrent l’influence de l’origine du prélèvement de la matière organique sur le type de molécules complexantes. Cette étude montre, également, que la vectorisation des actinides par la matière organique résulte d’une interaction avec un ensemble de molécules présentant des affinités plus ou moins forte pour le métal. Ces résultats semblent être en accord avec les modélisations macroscopiques NICA-DONNAN (approches continue) utilisés actuellement
Large amount of plutonium has been introduced into the environment as a result of nuclear weapons testing, and nuclear power-plant accidents. Contaminated areas, which need a particular survey, have become a very interesting place to study and understand the plutonium behaviour in the environment. Until few years ago, it was admitted that plutonium introduced into subsurface environment is relatively immobile, owing to its low solubility in ground water and strong sorption onto rocks. However, studies of contaminated areas show that humic substances, which are ubiquitous in environment, can alter the speciation of metal ion, e.g. plutonium, and thus their migration. These humic substances are major components of the natural organic matter in soil and water as well as in geological organic deposits such as lake sediments, peats and brown coals. They are complex heterogeneous mixtures of polydispersed supra-molecules formed by biochemical and chemical reactions during the decay and transformation of plant and microbial remains. The knowledge of the impact of humic substances on the plutonium migration is required to assess their transport in natural systems. However, due to the complex and heterogeneous nature of humic substances, there are a lot of difficulties in the description of microscopic interactions. The aim of this PhD thesis is to evaluate as precisely as possible interactions between actinides and humic substances. This work is divided in two parts: on the one hand humic substances will be separated to identify each component, on the other hand the speciation of actinides with characterized humic substances will be studied. In the first part of this study, new methods are developed to study the speciation of actinides with humic substances using two kinds of mass spectrometers: an ICP-MS and a high resolution mass spectrometer using various ionization devices (ESI, APCI, DART, APPI) in order to determine all active molecules for the complexation.In the second part, a new way of humic substances separation had been developed using an electrophoresis capillary apparatus. This efficient separation technique allows to simplify the characterisation of the complex heterogeneous mixtures without changing speciation of the chemical system.This study will lead to point out some molecules responsible for complexation of actinides by the humic substances

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Nickum, Elisa A. "Analysis of Regulated Drugs Using Chromatographic and Spectrophotometric Techniques Coupled with Spectroscopy An Orthogonal Approach to Protecting Public Health." University of Cincinnati / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1504799568245931.

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Neumaier, Marco. "FT-ICR-MS Studien zur Reaktivität kationischer Münzmetallcluster und zur elektronischen Stabilität von Fullerenanionen." Karlsruhe Forschungszentrum Karlsruhe, 2007. http://d-nb.info/989564908/34.

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Vasconcelos, Géssica Adriana. "Estendendo a caracterização dos compostos nitrogenados em resíduo de vácuo por FT-ICR MS." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/5952.

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Outro
Petroleomics by FT-ICR MS was able to characterize petroleum and its derivatives at molecular level. The most used ionization source on the analysis of these compounds is electrospray. However, species that are more basic or more acidic suppress the ionization of other compounds with less strength. This disadvantage consists of, especially in positive mode, only detecting compounds with higher pKa values preventing the mass spectrometer from reading less basic species that is also present in the sample. In view of this, the development of new methods whose purpose is to minimize these effects is essential. An alternative is to use fast techniques of extraction and separation followed by analysis by FT-ICR MS. This study pursued two goals: first, to perform an extraction of vacuum residue into basic and neutral nitrogen compounds using different methods, and second, to fractionate the basic nitrogen compounds present in RV according to their mass/ratio. Three methods were tested to achieve the first objective: solvent extraction (LLE), column chromatography (LC), and solid phase extraction (SPE). The results showed that LLE was the less selective technique among all three studied procedures. SPE and LC showed similar results, and they allowed to partially separate the basic nitrogen compounds from neutral species. To accomplish the second goal, a fractionation using SPE was applied to the vacuum residue sample. This procedure permitted to detect compounds that apparently were not present in the untreated sample as a consequence of a reduction on ion suppression effect. Electrospray ionization and high resolution mass spectrometry (FT-ICR MS) were employed on the analysis of each sample.
A petroleômica por FT-ICR MS foi capaz de caracterizar o petróleo e seus diferentes derivados a nível molecular. A fonte de ionização mais utilizada na análise destes compostos é o electrospray. Componentes mais básicos e mais ácidos, entretanto, suprimem a ionização de outras espécies com menor força. A grande desvantagem deste fato consiste, especialmente no modo positivo, detectar somente os compostos com elevado pKa impedindo a leitura das espécies menos básicas presentes na mesma amostra. À vista disso, é fundamental o desenvolvimento de novos métodos que tenham por finalidade minimizar estes efeitos. Uma alternativa é fazer o uso de técnicas rápidas de extração e separação seguida pelas análises por FT- ICR MS. Desta forma, este estudo teve dois objetivos principais: primeiro, realizar uma extração dos compostos nitrogenados de resíduo de vácuo em suas frações básica e neutra utilizando diferentes métodos e, segundo realizar um fracionamento dos compostos nitrogenados básicos presentes em RV de acordo com a sua massa. Para se alcançar o primeiro objetivo, três métodos foram testados: Extração líquido-líquido (LLE), cromatografia em coluna clássica (LC) e extração em fase sólida (SPE). Os resultados mostraram que o LLE foi a menos seletiva dentre os três procedimentos estudados. SPE e LC apresentaram resultados semelhantes e foi possível separar parcialmente os compostos básicos das espécies neutras. Para alcançar o segundo objetivo, um fracionamento utilizando extração em fase sólida foi empregado na amostra de resíduo de vácuo. Este procedimento permitiu detectar compostos que aparentemente não estavam presentes na amostra não tratada como consequência da redução do efeito de supressão iônica. A ionização por electrospray e por espectrometria de massa de alta resolução (FT-ICR MS) foram utilizados na análise de cada amostra.

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Neumaier, Marco. "FT-ICR-MS Studien zur Reaktivität kationischer Münzmetallcluster und zur elektronischen Stabilität von Fullerenanionen." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000007410.

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Nascimento, Iendel Rubio do. "Identificação Química em Nível Molecular de Amostras de Maconha por ESI-FT-ICR MS." reponame:Repositório Institucional da UFES, 2014. http://repositorio.ufes.br/handle/10/1233.

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mais consumida no país, e proscrita pela Lei n° 11.343 de 23 de agosto de 2006 (chamada de “nova lei de droga”), onde todos os isômeros, sais, éteres e ésteres do ∆9-Tetrahidrocannabinol (THC), princípio ativo, foram proscritos. O método utilizado pela Polícia Civil do Estado do Espírito Santo para a identificação de cannabinóides é o teste colorimétrico, por meio de solução básica de Salt Fast Blue B, o qual apresenta resultados falsos negativos e falsos positivos. A técnica de espectrometria de massas de altíssima resolução e exatidão de massas (ESI(-)FTICR MS), permite detectar os principais cannabinóides na forma de molécula desprotonada, íon [M-H]-. Alguns íons que podem ser identificados são: [CBN - H]- de m/z 309 (CBN = cannabinol); [THC - H]- de m/z 313 (THC = tetrahidrocannabinol) e [CBD - H]- de m/z 313; [CBC - H]- de m/z 327 (CBC = cannabicromeno); [CBEA - H]- de m/z 345 (CBEA = ácido cannabielsóico); [CBNA - H]- de m/z 353 (CBNA = ácido cannabinólico); [THCA - H]- de m/z 357 (THCA = ácido tetrahidrocannabinólico); [8α, 11-Bis-hydroxy-∆9-THC-A - H]- de m/z 389); [∆9-THCA +C2H2O - H]- de m/z 357; e dímeros com m/z de 637, 653, 673, 681, 685 e 717. Foram encontrados adulterantes identificados como [M + N + H]+ : 491; [2M + N + H]+ : 819 e [3M + N + H]+ : 1147, onde M = OTHC (328Da C21H28O3) e N = Nicotina (162Da C10H14N2), além de lidocaína e cocaína. Ainda foram identificados alguns noncannabinóides como Cannflavino A e B e ácidos graxos como palmítico, oleico, linolênico e gama-linolênico nos extratos de sementes de Cannabis. Este estudo tem o objetivo de identificar o perfil químico de amostras de maconha, apreendidas pela Polícia Civil do Estado do Espírito Santo, por ESI(±)-FT-ICR MS.
The Cannabis sativa L. is well known in Brazil as "maconha". This is the most consumed drug in this country, proscribed by the Law number 11.343 of 23rd August 2006(called "new drug law) , where all isomers, salts, ethers and esters of ∆9Tetrahidrocannabinol (THC), active principle, were proscribed. The method used by the Civil Police of Espírito Santo state to identify the cannabinoids is the test called "colorimetric. It is used by a basic solution of Salt Fast Blue B, which presents results false negatives and false positive. The technic of mass spectrometry of high solution and mass accuracies, ESI(-)FT-ICR MS, allows to detect the main cannabinoids in the form of molecules deprotonated , ions [M-H]. Some ions that can be identified are: [CBN-H]- of m/z 309 (CBN = cannabinol); [THC - H]- of m/z 313 (THC = tetrahidrocannabinol) and [CBD - H]- of m/z 313; [CBC –H]- of 327 (CBC = cannabicromeno); [CBEA - H]- of m/z 345 (CBEA = acid cannabielsóico); [CBNA - H] of m/z 353 (CBEA = acid cannabinólico); [THCA-H] de m/z 357 (THCA = acid tetrahidrocannabinólico); [8α,11-Bis-hydroxy-∆9-THC-A - H]- de m/z 389); [∆9-THCA +C2H2O - H]- of m/z 357; and dimers with m/z 637, 653, 673, 681, 685 and 717. Identified as contaminants found: [M + H]+: 491; [2M + N + H]+: 819; [3M + N + H]+: 1147, where M = OTHC (328Da C21H28O3) and N is nicotine (C10H14N2 162Da) beyond lidocaine and cocaine. Still some noncannabinóides were identified as: Cannflavino A and B and fatty acids such as palmitic, oleic, linoleic and gammalinolenic acid in the extracts of cannabis seeds. This study has the purpose to identify the chemical profile from samples of cannabis seized by the Civil Police from Espirito Santo state, by ESI(±)-FT-ICR MS.

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NASCIMENTO, I. R. "Identificação Química a Nível Molecular de Amostras de Maconha por ESI-FT-ICR MS." Universidade Federal do Espírito Santo, 2014. http://repositorio.ufes.br/handle/10/4706.

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A planta Cannabis sativa L. é conhecida no Brasil como maconha, sendo a droga mais consumida no país, e proscrita pela Lei n° 11.343 de 23 de agosto de 2006 (chamada de nova lei de droga), onde todos os isômeros, sais, éteres e ésteres do ∆9-Tetrahidrocannabinol (THC), princípio ativo, foram proscritos. O método utilizado pela Polícia Civil do Estado do Espírito Santo para a identificação de cannabinóides é o teste colorimétrico, por meio de solução básica de Salt Fast Blue B, o qual apresenta resultados falsos negativos e falsos positivos. A técnica de espectrometria de massas de altíssima resolução e exatidão de massas (ESI(-)FT-ICR MS), permite detectar os principais cannabinóides na forma de molécula desprotonada, íon [M-H]-. Alguns íons que podem ser identificados são: [CBN - H]- de m/z 309 (CBN = cannabinol); [THC - H]- de m/z 313 (THC = tetrahidrocannabinol) e [CBD - H]- de m/z 313; [CBC - H]- de m/z 327 (CBC = cannabicromeno); [CBEA - H]- de m/z 345 (CBEA = ácido cannabielsóico); [CBNA - H]- de m/z 353 (CBNA = ácido cannabinólico); [THCA - H]- de m/z 357 (THCA = ácido tetrahidrocannabinólico); [8α, 11-Bis-hydroxy-∆9-THC-A - H]- de m/z 389); [∆9-THCA +C2H2O - H]- de m/z 357; e dímeros com m/z de 637, 653, 673, 681, 685 e 717. Foram encontrados adulterantes identificados como [M + N + H]+ : 491; [2M + N + H]+ : 819 e [3M + N + H]+ : 1147, onde M = OTHC (328Da C21H28O3) e N = Nicotina (162Da C10H14N2), além de lidocaína e cocaína. Ainda foram identificados alguns noncannabinóides como Cannflavino A e B e ácidos graxos como palmítico, oleico, linolênico e gama-linolênico nos extratos de sementes de Cannabis. Este estudo tem o objetivo de identificar o perfil químico de amostras de maconha, apreendidas pela Polícia Civil do Estado do Espírito Santo, por ESI(±)-FT-ICR MS.

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Scherling, Christian. "Environmental Metabolomics - Metabolomische Studien zu Biodiversität, phänotypischer Plastizität und biotischen Wechselwirkungen von Pflanzen." Phd thesis, Universität Potsdam, 2009. http://opus.kobv.de/ubp/volltexte/2009/3241/.

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Ein genereller Ansatz zur Charakterisierung von biologischen Systemen bietet die Untersuchung des Metaboloms, dessen Analyse als „Metabolomics“ bezeichnet wird. “Omics”- Technologien haben das Ziel, ohne Selektionskriterien möglichst alle Bestandteile einer biologischen Probe zu detektieren (identifizieren und quantifizieren), um daraus Rückschlüsse auf nicht vorhersehbare und somit neuartige Korrelationen in biologischen Systemen zu ziehen. Ein zentrales Dogma in der Biologie besteht in der Kausalität zwischen Gen – Enzym – Metabolite. Perturbationen auf einer Ebene rufen systemische Antworten hervor, die in einem veränderten Phänotyp münden können. Metabolite sind die Endprodukte von zellulären regulatorischen Prozessen, deren Abundanz durch die Resonanz auf genetische Modifikationen oder Umwelteinflüsse zurückzuführen ist. Zudem repräsentieren Metabolite ultimativ den Phänotyp eines Organismus und haben die Fähigkeit als Biomarker zu fungieren. Die integrale Analyse verschiedenster Stoffwechselwegen wie Krebszyklus, Pentosephosphatzyklus oder Calvinzyklus offeriert die Identifikation von metabolischen Mustern. In dieser Arbeit wurden sowohl das targeted Profiling via GC-TOF-MS als auch das untargeted Profiling via GC-TOF-MS und LC-FT-MS als analytische Strategien genutzt, um biologische Systeme anhand ihrer Metabolite zu charakterisieren und um physiologische Muster als Resonanz auf endogene oder exogene Stimuli zu erkennen. Dabei standen die metabolische, phänotypische und genotypische Plastizität von Pflanzen im Fokus der Untersuchungen. Metabolische Varianzen eines Phänotyps reflektieren die genotyp-abhängige Resonanz des Organismus auf umweltbedingte Parameter (abiotischer und biotischer Stress, Entwicklung) und können mit sensitiven Metabolite Profiling Methoden determiniert werden. Diese Anwendungen haben unter anderem auch zum Begriff des „Environmental Metabolomics“ geführt. In Kapitel 2 wurde der Einfluss biotischer Interaktionen von endophytischen Bakterien auf den Metabolismus von Pappelklonen untersucht; Kapitel 3 betrachtet die metabolische Plastizität von Pflanzen im Freiland auf veränderte biotische Interaktionsmuster (Konkurrenz/Diversität/Artenzusammensetzung); Abschließend wurde in Kapitel 4 der Einfluss von spezifischen genetischen Modifikationen an Peroxisomen und den daraus resultierenden veränderten metabolischen Fluss der Photorespiration dargestellt. Aufgrund der sensitiven Analyse- Technik konnten metabolische Phänotypen, die nicht zwingend in einen morphologischen Phänotyp mündeten, in drei biologischen Systemen identifiziert und in einen stoffwechselphysiologischen Kontext gestellt werden. Die drei untersuchten biologischen Systeme – in vitro- Pappeln, Grünland- Arten (Arrhenatherion-Gesellschaft) und der Modellorganismus (Arabidopsis) – belegten anschaulich die Plastizität des Metabolismus der Arten, welche durch endogene oder exogene Faktoren erzeugt wurden.
A general approach to characterise biological systems offers the analysis of the metabolome, named “metabolomics”. “Omics”- technologies are untargeted approaches without any selection criteria which aim to detect every potential analyte in a sample in order to draw conclusions about new correlations in biological systems. A central dogma in biology is the causality between gene – enzyme – metabolite. Perturbations on one level are reflected in systemic response, which possibly result in a changed phenotype. Metabolites are end products of its gene expression and metabolism, whose abundance is determined as a resonance of genetic modifications or environmental disturbance. Furthermore metabolites represent the ultimate phenotype of an organism and are able to act as a biomarker. The integral analysis of distinct metabolic pathways like TCA, Pentose phosphate and Calvin cycle consequently leads to the identification of metabolic patterns. In this work targeted profiling via GC-TOF-MS as well as untargeted profiling via GC-TOF-MS and LC-FT-MS were used as analytical strategies to characterise biological systems on the basis of their metabolites and to identify physiological patterns as resonance of endogenic or exogenic stimuli. The focus of the investigations concentrates on the metabolic, phenotypic and genotypic plasticity of plants. Metabolic variance of a phenotype is reflected in the genotypic dependence response of an organism on environmental parameters which may be detected via sensitive metabolic profiling methods. In chapter 2 the influence of biotic interaction of endophytic bacteria on the metabolism of their poplar host was analyzed; chapter 3 explores the metabolic plasticity of field-grown grassland species as a consequence of biotic interaction pattern (competition / diversity / species composition); In conclusion, chapter 4 illustrates the influence of specific genetic modifications on peroxisomes and the consequent changed metabolic flux in the photorespiration pathway. Due to the sensitive analytic methods, metabolic phenotypes in all three biological systems could be identified and classified in a physiological context. The three biological systems – in vitro poplar plants, field-grown grassland species and the model organism Arabidopsis – demonstrate the plasticity of the metabolism of species in response to stimuli.

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OGAWA, E. M. "Perfil Químico Associado ao Diferentes Estádios de Maturação do Abacaxi cv. Vitória Por ESI(-)-FT-ICR MS e Estudo de Suas Atividades Biológicas na Químioprevenção de Câncer." Universidade Federal do Espírito Santo, 2016. http://repositorio.ufes.br/handle/10/4752.

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O abacaxi é o fruto do abacaxizeiro (Ananas comosus (L.) Merril), uma planta de clima tropical, perene, monocotiledônea, pertencente à família Bromeliaceae.1 O fruto é constituído por 100 a 200 frutilhos fundidos entre si sobre um eixo central. O sabor característico doce/azedo o torna amplamente apreciado pelos consumidores em todo o mundo. Além disso, ele também é usado por seus efeitos medicinais por apresentar a bromelina, uma enzima proteolítica com atividades farmacológicas, tais como anti-inflamatórias e inibição da agregação plaquetária. Além dessa protease, polissacarídeos são outras macromoléculas responsáveis pelos benefícios do abacaxi. A fibra da casca do fruto pode encurtar o tempo de trânsito gastrointestinal e melhorar o crescimento de pro-bióticos no intestino.2 Trata-se de uma fruta que possui elevado teor energético, devido à sua alta composição de carboidratos, e valor nutritivo pela presença de sais minerais (cálcio, potássio, fósforo, magnésio, sódio, cobre e iodo) e de vitaminas, principalmente ácido ascórbico, niacina, tiamina, riboflavina.1 O fruto é utilizado tanto para o consumo in natura quanto industrializado, em diferentes formas: pedaços em calda, suco, pedaços cristalizados e geleias.

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Pudenzi, Marcos Albieri 1990. "Petroleômica por FT-ICR MS : avaliando a eficiência da ionização dos compostos polares de petróleo." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248688.

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Orientador: Marcos Nogueira Eberlin
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Esse trabalho tem como objetivo conhecer e avaliar a ionização dos compostos polares no petróleo for Espectrometria de Massas por Ressonância Ciclotrônica de Íons com Transformada de Fourier (FTICR MS do inglês Fourier Transform Ion Cyclotron Resonance Mass Spectrometry), relacionando essa ionização com parâmetros experimentais e características intrínsecas das moléculas. No Capítulo 1 o tipo de amostra de interesse (petróleo) é abordado, tanto em suas características quanto em sua análise, definindo petroleômica e sua função. A espectrometria de massas é apresentada, então, como ferramenta de grande utilidade nos estudos petroleômicos, em especial aquela de ultra alta resolução como FTICR MS (Fourier Transform Ion Cyclotron Resonance Mass Spectrometry) acoplada a fonte de ionização eletrospray (ESI). No Capítulo 2 a ferramenta estatística do planejamento de experimentos é apresentada e, então, utilizada em uma amostra real de petróleo de forma a relacionar os parâmetros operacionais da fonte de ESI com respostas avaliadas comumente em petroleômica. Aspectos interessantes das relações parâmetro-resposta surgem durante o estudo, mostrando que a análise de petróleo por ESI-FTICR MS, apesar de largamente utilizada na literatura, não é trivial e precauções devem ser tomadas durante a otimização dos parâmetros experimentais. No Capítulo 3 as técnicas de APCI (Atmospheric Pressure Chemical Ionization) e APPI (Atmospheric Pressure PhotoIonization) são abordadas e utilizadas, juntamente com ESI, para avaliar a ionização de padrões de compostos similares àqueles encontrados nas principais classes de compostos polares do petróleo. A análise pelas técnicas que ionizam de forma mais abrangente os compostos apresentaram comportamentos que tornam tais análises inviáveis. Uma reação de metilação que melhora a ionização de compostos sulfurados também é realizada em duas condições, comparando-se tais condições a partir dos espectros obtidos após suas análises. Conhecendo a ionização desses compostos padrões, é possível entender a petroleômica de forma mais ampla dando maior confiabilidade para estabelecer as relações composição-comportamento do petróleo
Abstract: The aim of this work is to know and evaluate the crude oil polar compounds ionization through Fourier Transform Ion Cyclotron Resonance Mass Spectrometry, relating this ionization with experimental parameters and intrinsic characteristics of molecules. On Chapter 1 the sample of interest (crude oil) is addressed, both in its characteristics and its analysis, defining petroleomics and its function. Mass spectrometry is then presented as a tool of great utility in petroleomic studies, in special the ultra high resolution one as FTICR MS coupled to eletrospray Ionization (ESI). On Chapter 2 the design of experiment statistic tool is presented and used in a real crude oil sample in order to relate operational parameters of ESI source to commonly evaluated responses in petroleomics. Interesting aspects regarding parameter-response relationships arises during the study, showing that the crude oil analysis using ESI-FTICR MS, while it is largely used in literature, it is not trivial and precautions have to be taken during the optimization of experimental parameters. On Chapter 3 APCI (Atmospheric Pressure Chemical Ionization) and APPI (Atmospheric Pressure PhotoIonization) technics are addressed and used, along with ESI, to evaluate the ionization of standard compounds similar to those polar compounds found in crude oil. Analysis using sources that ionizes in the most comprehensive way has shown such behavior that makes the analysis unviable. A methylation reaction that improves the ionization of sulfur compounds is also made on two conditions, comparing these conditions through the obtained spectra after their analysis. By knowing the ionization of these standard compounds it is possible to understand the petroleomics in a much comprehensive way, providing reliability to stablish composition-behavior relations of crude oil
Mestrado
Quimica Organica
Mestre em Química

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Pereira, Rosana Cardoso Lopes 1959. "Petroleômica : caracterização de petróleos nacionais por espectrometria de massas de altíssima resolução: que os compostos ácidos podem revelar sobre o petróleo." [s.n.], 2012. http://repositorio.unicamp.br/jspui/handle/REPOSIP/248713.

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Orientadores: Marcos Nogueira Eberlin, Eugenio Vaz dos Santos Neto
Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química
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Resumo: Este trabalho consistiu na aplicação de tecnologia que se encontra hoje na vanguarda do conhecimento: a Petroleômica via ESI FT-ICR MS, com o objetivo de caracterizar as mais diversas classes de compostos polares ácidos presentes em amostras representativas de óleos de bacias brasileiras. O propósito ambicioso foi o de focalizar aspectos relacionados à toda cadeia de valor da indústria do petróleo, desde a geração do óleo até o seu refino, visando contribuir para novos estudos de interesse às atividades de upstream e downstream da PETROBRAS e, principalmente, fomentar a integração dos conhecimentos das diferentes áreas, o que contribuirá para ganhos de produtividade da empresa. A técnica ESI FT-ICR-MS mostrou-se uma técnica rápida e adequada para acompanhar as alterações verificadas na composição de amostras de petróleo, fornecendo subsídios a partir de uma caracterização única, para estudos diversos, abrangendo toda a cadeia de valor da indústria do petróleo. As alterações composicionais de óleos e extratos obtidos em experimentos de maturação artificial por hidropirólise de matéria orgânica dos tipos I e III foram avaliadas, evidenciando o potencial da técnica para utilização em estudos cinéticos. O estudo de biodegradação utilizando trinta amostras de óleos da Bacia Potiguar evidenciou que a técnica é sensível as variações de composição dos compostos polares que ocorrem em função do processo de biodegradação, e as amostras puderam ser agrupadas de acordo com o grau de biodegradação através da utilização de ferramentas quimiométricas (PCA). A partir dos dados de caracterização obtidos por ESI FT-ICR MS, foi possível agregar informações úteis para o entendimento de comportamentos diferenciados frente à tendência de formação de emulsão/gel durante a produção e frente à corrosão durante o refino
Abstract: This work focuses on the application of a technology that is cutting edge: Petroleomics by ESI FT-ICR MS with the goal of characterizing the large variety of acidic polar compound classes present in representative petroleum samples from Brazilian basins. The ambitious proposal was to focus on aspects related to the whole petroleum industry chain, since crude oil generation up to its processing in refinery units, to contribute to state-of-the-art studies of interest to upstream and downstream activities in PETROBRAS and mostly to encourage the knowledge integration, i.e. to form or blend the information into a whole, to UNITE, accessing high levels of productivity. The ESI FT-ICR MS technique exhibits characteristics like fast response, resolution, selectivity and sensibility, which make it suitable to monitor the changes in composition of petroleum samples and because of its unique and comprehensive characterization attained, to help different studies in the whole petroleum industry chain. The compositional alteration observed in extracts and oils during artificial maturation experiments by hydrouspyrolysis of organic matter types I and III were evaluated showing the potential of the technique to kinetic studies. Biodegradation studies were performed on 30 petroleum samples from Potiguar Basin and the results showed that the technique is sensitive to the variations on the composition of the polar compounds that occur as a result of the biodegradation process, and additionally, that the samples can be grouped according to their biodegradation level by the use of chimiometric tools (PCA). Also from the characterization data from ESI FT-ICR MS analysis it was shown that very useful information can be provided to better understand the differences in the rheological and corrosion behaviors of petroleum samples
Doutorado
Quimica Analitica
Doutora em Ciências

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Carvalho, Verônica Vale. "Caracterização química das frações de N-metil-pirrolidona de asfaltenos por espectrometria de massas de Ressonância Ciclotrônica de Íons com Transformada de Fourier." Universidade Federal de Goiás, 2016. http://repositorio.bc.ufg.br/tede/handle/tede/5835.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES
Heavy oil fractions studies are of great importance for the oil industry, receiving special attention in recent decades due to the interest to meet them in order to obtain compounds with higher added value derived from this. Moreover, these studies also aim solutions to the problems caused by these fractions during all processing steps oil. Asphaltenes in NMP produces two fractions, a soluble and the other insoluble in NMP. It was suggested that the NI fraction present low content of aromatic compounds, opening a new debate on the composition of asphaltenes which are widely discussed in the literature as aromatic and polar compounds. In the present work is the chemical study of these asphaltenes fractions by mass spectrometry of high resolution mass and accuracy, making use of the resonance cyclotron Ion Fourier Transform (FT-ICR MS) associated with the source of atmospheric pressure ionization - ESI (electrospray ionization), infrared, fluorescence and 1H NMR. The infrared analysis, 1H NMR and Fluorescence made it possible to observe differences among samples, where NS fraction had higher amounts of heteroatoms present and a higher percentage of aromatic hydrogens and NI fraction is nonpolar in the presence of increasing amounts of alkyl and naphthenic hydrocarbons. The results of FT-ICR MS corroborated with the other results, showing that the NS fractions showed high proportion of heteroatomics species and higher DBE values compared NI fractions exhibited predominantly hydrocarbon compounds and derisory amounts of heteroatoms and also insignificant quantities compounds of DBE values different from zero.
Os estudos das frações pesadas do petróleo são de grande importância para a indústria petrolífera, recebendo atenção especial nas últimas décadas devido ao interesse em conhecê-las visando a obtenção de compostos com maior valor agregado oriundos desta. Por outro lado, estes estudos também objetivam soluções para os problemas causados por essas frações durante todas as etapas de processamento do petróleo. Os asfaltenos em NMP produzem duas frações, uma solúvel e outra insolúvel em NMP. Foi sugerido que a fração NI apresente baixo teor de compostos aromáticos, abrindo um novo debate sobre a composição dos asfaltenos que são largamente discutidos na literatura como compostos aromáticos e polares. No presente trabalho realizou-se o estudo químico destas frações de asfaltenos por espectrometria de massas de altíssima resolução e exatidão, fazendo uso da Ressonância Ciclotrônica de Íons com Transformada de Fourier, (FT-ICR MS) associada com a fonte de ionização a pressão atmosférica – ESI (ionização por electrospray), infravermelho, fluorescência e RMN de 1H. As análises de infravermelho, RMN de 1H e fluorescência, possibilitaram observar as diferenças existentes entre as amostras, onde a fração NS apresentou maiores quantidades de heteroátomos presentes e maior porcentagem de hidrogênios aromáticos e a fração NI se mostrou apolar com a presença de maiores quantidades de hidrocarbonetos alquílicos e naftênicos. Os resultados de FT-ICR MS corroboraram com os demais resultados, evidenciando que, as frações NS apresentaram elevada proporção de espécies heteroatômicas e maiores valores de DBE quando comparadas as frações NI que exibiram predominância de compostos hidrocarbonetos e quantidades irrisórias de heteroátomos e também quantidades insignificantes de compostos com valores de DBE diferentes de zero.

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Neumaier, Marco [Verfasser]. "FT-ICR-MS-Studien zur Reaktivität kationischer Münzmetallcluster und zur elektronischen Stabilität von Fullerenanionen / Marco Neumaier." Karlsruhe : Forschungszentrum Karlsruhe, 2008. http://d-nb.info/989564908/34.

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Duriez, Elodie. "Développement de méthodes de détection (spectrométrie de masse, immunologie et biointeractions) de toxines protéiques utilisables à des fins terroristes dans des échantillons environnementaux et biologiques." Paris 6, 2009. http://www.theses.fr/2009PA066635.

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Le bioterrorisme a imposé le développement de stratégies analytiques complémentaires qu’il convient de mettre en œuvre dans une optique de détection ou de diagnostic des agents potentiellement impliqués. La difficulté majeure repose sur leur grande diversité. Ce manuscrit met en évidence l'apport de la spectrométrie de masse au domaine de la biodéfense. La première partie est consacrée à la ricine. Deux méthodes de détection ont été développées, impliquant la spectrométrie de masse combinée à une extraction/concentration de l’échantillon par immunoaffinité. La première méthode est un test d’activité enzymatique, spécifique de la forme fonctionnelle de la ricine et exploitant sa forte activité catalytique pour atteindre une sensibilité similaire aux techniques ELISA. La deuxième approche est de type protéomique, moins sensible mais spécifique de l’intégrité structurale de la ricine, par suivi de peptides générés par protéolyse enzymatique. Une étude sur la présence de variants structuraux a également été menée, et des essais complémentaires ont démontré l'applicabilité de ces méthodes à des échantillons complexes et à une vingtaine de ricines d’espèces différentes. En deuxième partie est présenté un test d’activité enzymatique du facteur oedématogène pour un diagnostic précoce de la présence de Bacillus anthracis. Deux méthodes analytiques complémentaires ont été développées, un dosage immunologique très sensible (1 pg/mL) et une analyse LC-MS/MS plus spécifique. La faisabilité de ces méthodes a été montrée lors du dosage d’échantillons plasmatiques de souris infectées. Ces tests permettront l’étude de la physiopathologie de la production de toxines au cours de l’infection.

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Desprez, Alain. "Caractérisation moléculaire et élémentaire des produits pétroliers lourds." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3052.

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Les pétroles utilisés en raffinage étant de plus en plus lourds et chargés en métaux et hétéroélements, il est d’une grande importance pour les activités de raffinage de connaître la spéciation de ces espèces au sein des produits pétroliers et leurs comportements durant les procédés de raffinage. Afin d’apporter des réponses à cette problématique des techniques de caractérisation élémentaire et moléculaire ont été utilisées notamment par ICP MS Haute Résolution et FT ICR MS respectivement. Ces techniques analytiques sont appliquées à différents échantillons pétroliers provenant parfois de procédés de raffinage et les informations obtenues au niveau élémentaire et moléculaire sont utilisées de manières complémentaires pour améliorer notre compréhension des mécanismes se produisant au sein de nos échantillons durant les activités de raffinage
The crude oils available for the refining industry are heavier and heavier and more concentrated in metals and heteroelements. It is thus of great importance to study the speciation of these species within the petroleum products and their behavior during the refining processes. To answer that problematic, elemental and molecular characterization techniques have been used, mainly High Resolution ICP MS and FT ICR MS for the elemental and molecular characterization respectively. The analytical techniques quoted are used for the analysis of several petroleum products sometimes originating from refining processes and the information obtained at the elemental and molecular level are combined to improve our understanding of the mechanisms occurring within our samples during refining activities

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Perez, Hurtado Pilar. "FT-ICR-MS approach to monitor asparagine deamidation and its isomers products in collagen from ancient bones." Thesis, University of Warwick, 2013. http://wrap.warwick.ac.uk/57622/.

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This project investigates the use of ultrahigh resolution mass spectrometry along with fragmentation techniques such as electron capture dissociation (ECD) and collisionally activated dissociation (CAD) to study deamidation of ancient bone, by using potential deamidation markers present in bovine collagen standards. With the application of these techniques, several marker peptides present in the digested protein standard of bovine collagen were successfully assigned. The sequences of these peptides correlated well with the reported sequences for bovine collagen in the literature. FT-ICR-MS was used to monitor deamidation of collagen by following a shift of +0.948 Da in the spectrum, resulting in a mass difference of 19 mDa from the 13C of the non-deamidated form and the 12C of the deamidated form, which can be difficult to assign due to overlap with the 13C isotopic distribution in peptides. The rate constants for the deamidation reaction were calculated, and the extent of deamidation before sample handling was determined. The methodology developed was then applied to collagen extracted from real bone samples, both modern and ancient, proving to be a useful method for monitoring asparagine deamidation before sample preparation. Differentiation of the isomers products of deamidation (aspartic and isoaspartic acid) were successfully assigned (where possible) using the diagnostic ions originated from their ECD spectra.

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Oliveira, Letícia Pollo de. "Neospora caninum: estudo do secretoma e caracterização molecular de três proteínas com domínios Apple." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/60/60135/tde-18122013-155545/.

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Neospora caninum (filo Apicomplexa) é um parasita obrigatório intracelular como todos os membros deste filo, alguns reconhecidos por causarem doenças com impacto relevante na saúde humana (Plasmodium e Toxoplasma) e veterinária (Babesia, Eimeria e Cryptosporidium). Causador da neosporose, N. caninum vem emergindo como um dos maiores causadores de abortos infecciosos em bovinos, levando a consideráveis perdas econômicas na bovinocultura mundial. Devido à sua recente descoberta, o conhecimento sobre diversos processos bioquímicos de N.caninum ainda é limitado, demandando novas pesquisas para a compreensão de seus mecanismos de sobrevivência e consequente identificação de alvos para intervenção terapêutica. O processo de invasão celular é bastante investigado em pesquisas envolvendo apicomplexas, uma vez que a sobrevivência desses parasitas depende do sucesso de sua entrada na célula hospedeira. Proteínas secretadas de organelas filo-específicas (micronemas, roptrias e grânulos densos) estão intimamente envolvidas com a invasão celular. Elas são responsáveis pela interação inicial com a célula hospedeira, participam da junção de movimento formada no momento da invasão, e contribuem para a estabilização do vacúolo parasitóforo. Neste trabalho as proteínas secretadas por taquizoítas de N. caninum foram investigadas de duas formas: (1) por caracterização molecular de proteínas com domínio Apple; e (2) por estudo do secretoma do parasita. Os domínios proteicos do tipo Apple são caracterizados pela capacidade de interação proteína-proteína e proteína-carboidrato, e estão presentes em algumas proteínas micronêmicas com propriedades adesivas. Neste trabalho três proteínas de N. caninum contendo domínios Apple foram caracterizadas: MIC17A, MIC17B e MIC17C. A análise das sequências proteicas e das estruturas dos domínios Apple, obtidas por modelagem molecular, mostraram alta identidade sequencial e estrutural entre MIC17A e MIC17C. Apesar de ser paráloga às outras duas, MIC17B apresenta diferenças importantes em sua sequência e estrutura. Para MIC17B e MIC17C foram realizados experimentos de detecção das proteínas nativas nos extratos total e secretado do taquizoíta que sugerem diferentes formas de processamento entre essas proteínas no parasita. Para MIC17B foi confirmada a localização em micronemas, num padrão diferente do observado para MIC17C. Os ensaios de invasão combinados aos de localização indicam que estas proteínas estejam relacionadas ao processo de invasão celular, porém, suas funções permanecem desconhecidas. O secretoma é o conjunto de proteínas secretadas pelo parasita e, para explorar a composição deste extrato (ESA) no taquizoíta de N. caninum, duas abordagens complementares foram utilizadas. Na primeira abordagem foram identificadas as proteínas presentes no ESA por espectrometria de massas. Na segunda abordagem realizou-se uma ii quantificação relativa das proteínas, marcadas por dois isótopos, nos extratos totais de taquizoítas submetidos ou não ao estímulo secretório. O resultado esperado seria com as proteínas secretadas diminuídas no parasita estimulado. Em ambas as abordagens foram utilizadas técnicas de espectrometria de massas de alta resolução (nanoLC-MS/MS), o que resultou num alto número de identificações; 615 proteínas no ESA e 2011 proteínas quantificadas. A comparação das duas abordagens permitiu o reconhecimento de proteínas com maior probabilidade de secreção. Uma rede de interação entre as proteínas diferencialmente expressas foi predita, gerando resultados que, associados às informações sobre as proteínas aumentadas, permitiram uma investigação sobre proteínas potencialmente envolvidas com a regulação do metabolismo relacionado à secreção. Os resultados obtidos por ambos os estudos aqui demonstrados somam conhecimento acerca do parasita N. caninum e demonstram ser úteis para guiar a busca e seleção de alvos a serem investigados para o desenvolvimento de terapêutica contra a neosporose.
Neospora caninum (Apicomplexa phylum) is an obligatory intracellular parasite like all members from this phylum, some causing diseases with relevant impact on human (Plasmodium and Toxoplasma) and veterinary (Babesia, Eimeria and Cryptosporidium) health. Causative agent of neosporosis, N. caninum has emerged as one of the leading causes of infectious abortion in cattle, generating huge economical losses in worldwide livestock. Due to its recent discovery, knowledge of N. caninum biochemical processes remains scarce, demanding new research for comprehending its survival mechanisms and, consequently, identifying new targets for therapeutic intervention. The invasion process has often been investigated in apicomplexans since their survival depends on the success of their entry into the host cell. Proteins secreted from phylum-specific organelles (micronemes, rhoptries and dense granules) are deeply involved with invasion. They are responsible for the initial interaction with the host cell; participate of the moving junction formed in the moment of invasion; and contribute for the stabilization of the parasitophorus vacuole. In this study, the proteins secreted by N. caninum tachyzoites were investigated in two ways: (1) the molecular characterization of Apple domaincontaining proteins; and (2) exploring the parasite secretome. The Apple protein domains are characterized by the ability to interact as protein-protein and proteincarbohydrate, and are present in some microneme proteins with adhesive properties. Here three N. caninum proteins containing Apple domains were characterized: MIC17A, MIC17B and MIC17C. Analyses of the Apple domains sequences and structures, obtained by molecular modeling, revealed high sequential and structural identities between MIC17A and MIC17C. Although being a paralog of the other two proteins, MIC17B presents significant differences in its sequence and structure. Experiments were performed for native MIC17B and MIC17C detection in the total and secreted tachyzoite extracts, suggesting different processing forms for these proteins in the parasite. For MIC17B, the microneme localization was confirmed, differently from the pattern observed for MIC17C. Invasion and localization assays indicated that these proteins are related to the cell invasion process; nevertheless, their functions remain unknown. The secretome is the set of proteins secreted by the parasite and, to explore this extract (ESA) composition in N. caninum, two complementary approaches were used. Firstly proteins present in ESA were identified by mass spectrometry. In the second approach, a relative quantification was performed on the proteomes of ethanol stimulated/non stimulated tachyzoites, expecting that the secreted proteins would be down regulated at the stimulated parasite. Both approaches were performed with high resolution mass spectrometry techniques (nanoLC-MS/MS), reaching a high number of identifications: 615 proteins iv in ESA and 2011 quantified proteins. The comparison between both approaches allowed the recognition of the most likely secreted proteins. An interaction network was predicted, involving the differentially expressed proteins. These results, associated with the information of up regulated proteins, allowed the investigation of proteins potentially involved with the secretion metabolism regulation. The findings from our two studies add up knowledge about N. caninum and demonstrate to be useful in guiding the search and selection for new targets for therapeutic development against neosporosis.

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Alber, George Miles. "Theory and instrumentation for precise mass measurement by Fourier transform Ion Cyclotron Resonance Mass Spectrometry (FT/ICR/MS) /." The Ohio State University, 1992. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487777170408073.

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Dhuey, Elliot. "Investigation of Corrosion in Canned Tomatoes Processed by Retorting." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1565787909221938.

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Nicolaou-Markide, Nicoletta. "The use of analytical techniques for the rapid detection of microbial spoilage and adulteration in milk." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/the-use-of-analytical-techniques-for-the-rapid-detection-of-microbial-spoilage-and-adulteration-in-milk(014652ea-b404-4bd5-bd8b-5b91bcb06cff).html.

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Milk is an important nutritious component of our diet consumed by most humans on a daily basis. Microbiological spoilage affects its safe use and consumption, its organoleptic properties and is a major part of its quality control process. European Union legislation and the Hazard Analysis and the Critical Control Point (HACCP) system in the dairy industry are therefore in place to maintain both the safety and the quality of milk production in the dairy industry. A main limitation of currently used methods of milk spoilage detection in the dairy industry is the time-consuming and sometimes laborious turnover of results. Attenuated total reflectance (ATR) and high throughput (HT) Fourier transform infrared (FTIR) spectroscopy metabolic fingerprinting techniques were investigated for their speed and accuracy in the enumeration of viable bacteria in fresh pasteurized cows' milk. Data analysis was performed using principal component-discriminant function analysis (PC-DFA) and partial least squares (PLS) multivariate statistical techniques. Accurate viable microbial loads were rapidly obtained after minimal sample preparation, especially when FTIR was combined with PLS, making it a promising technique for routine use by the dairy industry. FTIR and Raman spectroscopies in combination with multivariate techniques were also explored as rapid detection and enumeration techniques of S. aureus, a common milk pathogen, and Lactococcus lactis subsp cremoris, a common lactic acid bacterium (LAB) and potential antagonist of S. aureus, in ultra-heat treatment milk. In addition, the potential growth interaction between the two organisms was investigated. FTIR spectroscopy in combination with PLS and kernel PLS (KPLS) appeared to have the greatest potential with good discrimination and enumeration attributes for the two bacterial species even when in co-culture without previous separation. Furthermore, it was shown that the metabolic effect of L. cremoris predominates when in co-culture with S. aureus in milk but with minimal converse growth interaction between the two microorganisms and therefore potential implications in the manufacture of dairy products using LAB. The widespread and high consumption of milk make it a target for potential financial gain through adulteration with cheaper products reducing quality, breaking labeling and patent laws and potentially leading to dire health consequences. The time consuming and laborious nature of currently used analytical techniques in milk authentication enabled the study of FTIR spectroscopy and matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-ToF-MS) as rapid analytical techniques in quantification of milk adulteration, using binary and tertiary fresh whole cows', goats' and sheep's milk mixture samples. Chemometric data analysis was performed using PLS and KPLS multivariate analyses. Overall, results indicated that both techniques have excellent enumeration and detection attributes for use in milk adulteration with good prospects for potential use in the dairy industry.

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Shi, Ruijan. "Influence of Weak Interactions on Supramolecular Binding: Characterization of Cucurbituril Complexes with Alkylmonoammonium Ions Using Fourier Transform Ion Cyclotron Resonance Mass Spectrometry." BYU ScholarsArchive, 2011. https://scholarsarchive.byu.edu/etd/2898.

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This thesis focuses on using mass spectrometry-based techniques for characterizing the structure and behavior of cucurbituril complexes in the gas phase. Both solvent and counter ion effects can be completely eliminated in the gas phase and the intrinsic interactions in the system are directly shown in the experimental results. Chapter 1 introduces the structures, properties and host-guest chemistry of cucurbituril, and FTICR mass spectrometry including instrumentation, performance and working principles. Two mass spectrometry-based methods for supramolecular characterization, sustained off-resonance irradiation collision induced dissociation (SORI CID) and ion molecule equilibrium measurements, are also discussed in this chapter. Chapter 2 characterizes the dissociation and reaction behaviors of the complexes formed by cucurbit[5]uril (CB5) and primary monoamines [CH3(CH2)nNH2, n = 0-7] as well as similar studies of decamethylcucurbit[5]uril (mc5) in the gas phase. This study probes host-guest interactions between the neutral cucurbituril host and alkyl chains of varying length. All the cucurbit[5]uril and decamethylcucurbit[5]uril complexes have external binding. The dissociation thresholds of the complexes suggest that the optimum monoammonium chain length for binding CB5 in the gas phase occurs for n = 2, whereas for mc5 the optimum is n = 0. Reactivity studies of CB5 and mc5 complexes indicate the highest binding affinity appears at n = 6 for CB5 and n = 5 for mc5. Chapter 3 investigates the complexes formed by cucurbit[6]uril and primary monoamines using energy resolved SORI CID methods and ion molecule equilibrium measurements. The fragmentation data, branching ratios for the various channels, and the reactivities of the complexes suggest the complexes have the monoammonium threaded through the cavity of CB6 forming a pseudorotaxane architecture. Reactivity studies of complexes of cucurbit[7]uril reveal behaviors distinctive from CB5, mc5 or CB6, which suggests both internally-bound and externally-bound structures are present in CB7 complexes.

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CORREIA, R. M. "Perfil Químico do Café Capixaba Conilon & Arábica Por ESI(-)FT-ICR MS e ATR-FTIR: uma Abordagem Quantitativa." Universidade Federal do Espírito Santo, 2016. http://repositorio.ufes.br/handle/10/7358.

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O Brasil é o maior produtor e segundo consumidor mundial de café, sendo o Espírito Santo um dos maiores pólos de produção nacional deste produto. O café é uma fruta de grande importância para o PIB do país e a presença de adulterantes infringe o direito do consumidor, causando-lhe prejuízos e possíveis danos à saúde. Desta maneira, desenvolver um método analítico para determinar possíveis adulterações, agregaria valor de commodity, fortalecendo o crescimento econômico do país. Amostras de café torrados Conilon e Arábica foram analisadas através da técnica de Espectrometria de Massas por Ressonância Ciclotrônica de Íons com Transformada de Fourier (ESI(-)FT-ICR MS) e Espectroscopia na região do infravermelho médio com refletância total atenuada (ATR-FTIR) com o objetivo de desenvolver um método de quantificação de café Conilon em blendas de café Arábica, utilizando modelos de análise de dados uni e multivariados. Para construção do modelo de calibração univariada por ESI(-)FT-ICR MS, foram usadas 10 amostras de café Arábica (Coffea Arábica) adulteradas com diferentes proporções de café Conilon (Coffea Canephora), e 2 amostras puras (0% e 100 wt% de café Conilon) dopadas com um padrão interno de ácido esteárico de concentração 5.10-3 mol.L-1 (m/z 283 e 567). Para a análise de ATR-FTIR foram usadas uma maior variabilidade de adulterações, totalizando 21 amostras de blendas e 2 amostras puras (0% e 100 wt% de café Conilon), a partir dos resultados foi proposto um modelo de regressão por mínimos quadrados parciais (PLS). A partir dos resultados de ESI(-)FT-ICR foi possível identificar as principais espécies químicas presentes nas amostras de cafés, tais como: ácido quínico (m/z 191), ácido cafeoilquínico (m/z 353) e ácido feruloilquínico (m/z 367). O modelo de calibração univariada desenvolvido apresentou boa linearidade (R2 de 0,976) e limites de detecção e de quantificação de 0.2 e 0.3 wt%, respectivamente. O modelo PLS construído com dados ATR-FTIR resultou em um RMSECV de 5.7 wt% e RMSEP de 9.2 wt%, com coeficientes de determinação para validação cruzada e previsão de 0.9635 e 0.9295, respectivamente. Foram encontrados valores de repetibilidade e precisão intermediária de 4 wt% e 5 wt% para ESI(-)FT-ICR MS respectivamente, e 1,7 wt% para ambas as figuras de mérito nas análises de ATR-FTIR.

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Colati, Keroly Alaíde Pascoal. "Extração e caracterização de ácidos naftênicos por espectrometria de massas de altíssima resolução e exatidão (ESI-FT-ICR MS)." Mestrado em Química, 2012. http://repositorio.ufes.br/handle/10/1951.

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COLATI, K. A. P. "Extração e Caracterização de Ácidos Naftênicos por Espectrometria de Massas de Altíssima Resolução e Exatidão (ESI-FT-ICR MS)." Universidade Federal do Espírito Santo, 2012. http://repositorio.ufes.br/handle/10/4672.

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Os ácidos naftênicos estão presentes nos óleos como uma mistura complexa que exibe grande variação estrutural. Esses compostos são os principais responsáveis por problemas de corrosão e pela formação de emulsões estáveis e depósitos indesejáveis. Uma forma clássica de se monitorar a acidez de petróleos é através do número de acidez total (NAT). O aumento do NAT é normalmente associado com a taxa de corrosão do óleo. Ácidos naftênicos podem ser obtidos a partir do óleo cru por processos de extração, como extração líquido/líquido com soluções alcalinas, extração sólido/líquido e outros. Métodos instrumentais de análise como a Espectroscopia no infravermelho (FTIR) e a Espectrometria de massas de altíssima resolução e exatidão acoplada a uma fonte de electrospray (ESI (-) FT-ICR MS) têm sido utilizadas para caracterização de componentes ácidos em petróleos. Diante disso, o principal objetivo deste trabalho foi caracterizar ácidos naftênicos extraídos de duas amostras (AM1 e AM2) de petróleos com alto valor de NAT utilizando a técnica ESI (-) FT-ICR MS. Ácidos naftênicos foram extraídos por meio de soluções alcoólicas alcalinas a pHs 7, 10 e 14. Foram realizadas análises de NAT nos óleos originais e residuais. Análises ESI (-) FT-ICR MS e FTIR foram feitas nos óleos originais, residuais e frações ácidas obtidas. O processo de extração foi bastante satisfatório mostrando uma redução do NAT de 92% para AM1 e 85% para AM2 ambas extraídas a pH 14. Foi verificado pelas análises de infravermelho a concentração de ácidos carboxílicos nas frações ácidas pelo aumento da absorção na região de 1706 cm-1. Foi observada também a presença de compostos nitrogenados pela absorção em 3380 cm-1. As análises ESI (-) FT-ICR MS mostraram que para ambas as amostras de óleo as espécies ácidas se concentram em um range de m/z de 200 a 600 Da com um máximo em aproximadamente 375 Da. As classes N, NO2 e O2 foram as mais abundantes para todas as amostras em estudo. As espécies O2 foram extraídas dos óleos originais se acumulando satisfatoriamente nos extratos ácidos. Classes O4 foram encontradas em baixa intensidade. Classes O8 não foram detectadas. As classes N permanecem, em sua maioria, nos resíduos migrando em pouca proporção para as frações ácidas 14. As espécies O2 contidas nas amostras de óleo apresentaram majoritariamente DBE na faixa de 3 a 4 não havendo mudança no decorrer do processo de extração. A faixa de número de carbonos desloca-se de C25-C44 do óleo original para C19-C34 nas frações ácidas obtidas a pH 14. Nos óleos residuais da amostra AM1 houve a detecção de espécies com DBE < 3 os quais não foram detectados no óleo original. O óleo residual obtido a pH 14 para a AM2 se mostrou com uma menor porção de ácidos naftênicos remanescentes do que o óleo residual obtido no mesmo pH para a amostra AM1. Houve um acúmulo de compostos O2 nas frações ácidas com o acréscimo de pH para todo o range de DBE fazendo-se presentes também classes N em quantidades apreciáveis somente para DBE 12 e 15.

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DALMASCHIO, G. P. "Caracterização de Compostos Polares no Petróleo por Espectrometria de Massas de Altíssima Resolução e Exatidão ESI(±)-FT-ICR MS." Universidade Federal do Espírito Santo, 2012. http://repositorio.ufes.br/handle/10/4673.

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O petróleo é considerado a mistura natural mais complexa do mundo e por apresentar milhares de constituintes é um das matérias-primas mais desafiadoras para as análises químicas. Embora muitas técnicas venham sendo utilizadas para a caracterização dos constituintes do óleo, quando combinamos o altíssimo poder de resolução e exatidão da espectrometria de massas, em especial a Ressonância Ciclotrônica de Íons por Transformada de Fourier, (FT-ICR MS) com fontes de ionização a pressão atmosférica ESI (ionização por electrospray), uma atribuição precisa de mais de 20 000 composições elementares de componentes orgânicos contendo heteroátomos do óleo cru pode ser obtida. Na indústria do petróleo existe um grande interesse na análise de ácidos naftênicos devido ao mecanismo de corrosão que ainda é uma questão bastante explorada. Ácidos naftênicos são grupos de ácidos carboxílicos de cadeia saturada podendo ser monocíclicos ou policíclicos, sendo o fenômeno de corrosão provocado principalmente por meio da reação química dessas espécies com o ferro, afetando diretamente vários processos da indústria petroquímica. Com o objetivo de estudar a composição polar de cortes de petróleo através do processo de destilação, medidas de ESI(±)FT-ICR MS foram realizadas e os resultados foram associados com os valores obtidos pelo número de acidez total (NAT). Adicionalmente, a ionização por ESI foi otimizada para compostos contendo enxofre (classe S1). Reações de metilação em cortes e resíduos de destilação a vácuo do petróleo foram realizadas e posteriormente, analisadas via ESI(+)-FT-ICR MS. Os resultados obtidos das análises de ESI(-)-FT-ICR MS mostraram a classe O2 (ácidos naftênicos) como sendo a classe majoritária nas frações. Além disso, o aumento da acidez com a temperatura de ebulição dos cortes é proporcional ao aumento da série homóloga, ao valor de DBE e à distribuição do número de carbono das espécies identificadas, o que sugere que em cortes de maior ponto de ebulição, moléculas mais complexas são encontradas em maiores concentrações. Com os resultados obtidos por ESI(+)-FT-ICR MS foi possível identificar a classe N1 como a classe mais abundante nos cortes destilados. As espécies sulfuradas e outros compostos orgânicos que apresentam em sua estrutura um sistema de duplas ligações conjugadas, como por exemplo, furanos, só puderam ser identificados após as reações de metilação.

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PEREIRA, T. M. C. "Aplicações de Espectrometria de Massas de Ressonância Ciclotrônica de Íons por Transformada de Fourier (FT-ICR MS) em Petroleômica." Universidade Federal do Espírito Santo, 2013. http://repositorio.ufes.br/handle/10/4692.

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O petróleo é uma mistura complexa, sendo uma das misturas mais desafiadoras para as análises químicas. Muitas técnicas são empregadas para a caracterização dos constituintes do óleo. Entretanto, quando combinamos o altíssimo poder de resolução e exatidão da espectrometria de massas, em especial a Ressonância Ciclotrônica de Íons com Transformada de Fourier, (FT-ICR MS) com fontes de ionização a pressão atmosférica, uma atribuição precisa demais de 20.000 compostos orgânicos do petróleo pode ser obtida. Na indústria do petróleo existe um grande interesse na análise de ácidos naftênicos e asfaltenos devido a problemas como corrosão e formação de depósitos, que aumentam os custos de produção. Portanto este trabalho tem como objetivo a avaliação da termodegradação de ácidos naftênicos, além do emprego das fontes de ESI, APCI, LDI e MALDI para aquisição de novos dados relativos a caracterização de asfaltenos. Dois petróleos foram utilizados nos ensaios de termodegradação, opetróleo A com acidez de 2,38 mg KOH g-1 e o petróleo B com 4,79 mg KOH g-1 os quais foram tratados a 280, 300 e 350 ºC pelo período de 2, 4 e 6 horas. De uma maneira geral, as principais classes identificadas para ambas as amostras foram O2, N e NO2, respectivamente. Uma leve redução do NAT e da abundância relativa referente à classe O2 foram observados em função da temperatura e do tempo de envelhecimento (T = 280 --> 300° C e t = 2 --> 6h), sendo que a temperatura de tratamento térmico a 350° C demonstrou-se determinante na remoção de compostos da classe O2. O perfil químico de amostras de asfaltenos brasileiros foi avaliado utilizando-se cinco diferentes métodos de ionização em ambos os modos de ionização: positivo e negativo, depois, a distribuição de peso molecular, distribuição de classe, parcelas típicas de número de carbono contra DBE e diagramas van Krevelen foram obtidos e discutidos. Um comportamento atípico foi observado para a fonte de LDI e MALDI (+_) FT-ICR MS. Um amplo perfil, de m/z 500-3000, apresentando espaçamento de 24 Da foi observado, e este corresponde a formas alotrópicas de fulereno, C60. Em geral, os asfaltenos apresentaram um elevada proporção de espécies heteroatómicas como: HC, HC [H], N, N [H], N2O, N2O [H], N2, N2 [H], O, O[H] para o modo(+) e N, N [H], NO, NO [H], NO, NO2[H], N2O, N2O[H] para o modo negativo. Nos diagramas de DBE contra o número de carbono, os asfaltenos mostraram para cada valor de DBE uma pequena amplitude de compostos com respeito à NC, proporcionando assim, imagens que formam uma linha de 45 ° entre os eixos CN e DBE. Isto indica que estes compostos não exibem grandes cadeias de alquílicas, sendo composta principalmente por anéis aromáticos. Em geral os diagramas de van Krevelen mostraram alta proporção de compostos com razão H/C ~0,7, corroborando com a existência de espécies altamente aromáticas.

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Pereira, Thieres Magaive Costa. "Aplicações da Espectrometria de Massas de Ressonância Ciclotrônica de Íons por Transformada de Fourier (FT-ICR MS) em Petroleômica." Universidade Federal do Espírito Santo, 2013. http://repositorio.ufes.br/handle/10/6748.

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O petróleo é uma mistura complexa, sendo uma das misturas mais desafiadoras para as análises químicas. Muitas técnicas são empregadas para a caracterização dos constituintes do óleo. Entretanto, quando combinamos o altíssimo poder de resolução e exatidão da espectrometria de massas, em especial a Ressonância Ciclotrônica de Íons com Transformada de Fourier, (FT-ICR MS) com fontes de ionização a pressão atmosférica, uma atribuição precisa de mais de 20 000 compostos orgânicos do petróleo pode ser obtida. Na indústria do petróleo existe um grande interesse na análise de ácidos naftênicos e asfaltenos devido a problemas como corrosão e formação de depósitos, que aumentam os custos de produção. Portanto este trabalho tem como objetivo a avaliação da termodegradação de ácidos naftênicos, além do emprego das fontes de ESI, APCI, APPI, LDI e MALDI para aquisição de novos dados relativos a caracterização de asfaltenos. Dois petróleos foram utilizados nos ensaios de termodegradação, o petróleo A com acidez de 2,38 mg KOH g-1 e o petróleo B com 4,79 mg KOH g-1 os quais foram tratados a 280, 300 e 350 ºC pelo período de 2, 4 e 6 horas. De uma maneira geral, as principais classes identificadas para ambas às amostras foram O2, N e NO2, respectivamente. Uma leve redução do NAT e da abundância relativa referente à classe O2 foram observado em função da temperatura e do tempo de envelhecimento (T = 280 → 300 oC e t = 2 → 6 h), sendo que a temperatura de tratamento térmico a 350 ºC demonstrou-se determinante na remoção de compostos da classe O2. O perfil químico de amostras de asfaltenos brasileiros foi avaliado utilizando-se cinco diferentes métodos de ionização em ambos os modos de ionização: positivo e negativo, depois, a distribuição de peso molecular, distribuição de classe, parcelas típicas de número de carbono contra DBE e diagramas van Krevelen foram obtidos e discutidos. Um comportamento atípico foi observado para a fonte de LDI e MALDI (±) FT-ICR MS. Um amplo perfil, de m/z 500-3000, apresentando espaçamento de 24 Da foi observado, e este corresponde a formas alotrópicas de fulereno, C60. Em geral, os asfaltenos apresentaram um elevada proporção de espécies heteroatómicas como: HC, HC [H], N, N [H], N2O, N2O [H], N2, N2 [H], O, O[H] para o modo (+) e N, N [H], NO, NO [H], NO, NO2[H], N2O, N2O[H] para o modo negativo. Nos diagramas de DBE contra o número de carbono, os asfaltenos mostraram para cada valor de DBE uma pequena amplitude de compostos com respeito à NC, proporcionando assim, imagens que formam uma linha de 45 ° entre os eixos CN e DBE. Isto indica que estes compostos não exibem grandes cadeias de alquílicas, sendo composta principalmente por anéis aromáticos. Em geral os diagramas de van Krevelen mostraram alta proporção de compostos com razão H/C ~0,7, corroborando com a existência de espécies altamente aromáticas
Petroleum is a complex mixture, being one of the most challenging mixtures for chemical analyzes. Many techniques are employed to characterize constituents of the oil. However , when we combine the highest resolving power and accuracy of mass spectrometry , especially Ion Cyclotron Resonance Fourier Transform ( FT - ICR MS ) with sources of atmospheric pressure ionization , an assignment need more than 20 000 organic compounds in the oil can be obtained. In the oil industry there is a great interest in the analysis of asphaltenes and naphthenic acids due to problems such as corrosion and deposit formation, which increases production costs. Therefore this study aims to evaluate the thermodegradation of naphthenic acids, besides the use of sources of ESI, APCI, APPI, MALDI and LDI for the acquisition of new data on the characterization of asphaltenes . Two test oils were used in thermodegradation of the oil with an acidity of 2.38 mg KOH g -1 and Oil B with 4.79 mg KOH g- 1 which were treated at 280 , 300 and 350 ° C for a period of 2 , 4 and 6 hours. Generally, the major classes identified for both samples O2, NO2, and C, respectively. A slight reduction of NAT and relative abundance refers to the class O2 were observed as a function of temperature and aging time (T = 280 → 300 ° C t = 2 → 6 h), and the heat treatment temperature at 350 ° C showed a determinant for the removal of class O2. The chemical asphaltenes Brazilian samples was evaluated using five different methods of ionization in both modes of ionization: positive and negative, then the molecular weight distribution, distribution class, typical plots versus carbon number and DBE van Krevelen diagrams were obtained and discussed. An unusual behavior was observed for the LDI and MALDI source ( ± ) FT - ICR MS . A comprehensive profile of m / z 500-3000, with spacing of 24 Da was observed, and this corresponds to allotropes of fullerene C60. In general, the asphaltenes had an heteroatómicas high proportion of species such as HC , HC [ H] , N, [ H] , N2O N2O [ H] N2, N2 [ M ] O O [ H] to mode (+) and N, [ H ] , NO [ H] , NO , NO2, [ H] , N2O N2O [ H ] for the negative mode . In the diagrams DBE against the carbon number , the asphaltenes shown for each value of DBE composed of a small amplitude with respect to NC, thus providing images that form a line of 45 ° between the axes CN and DBE. This indicates that these compounds do not exhibit large chain alkyl, composed mainly of aromatic rings. In general diagrams van Krevelen showed a high proportion of compounds ratio H / C ~ 0.7, confirming the existence of highly aromatic species

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Liu, Youzhong. "Etude des interactions levures/bactérie par métabolomique." Thesis, Dijon, 2015. http://www.theses.fr/2015DIJOS074/document.

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Le vin en tant qu’écosystème complexe est un modèle particulièrement intéressant pour l’étudie des interactions entre les microorganismes. L’interaction sans contact celluaire (interaction indirecte) entre la levure Saccharomyces cerevisae et la bactérie lactique Oenococcus oeni a un effect direct sur l’induction et l'achèvement de la fermentation malolactique (FML), une fermentation très importante pour la qualité du vin. Une souche levurienne peut être classée FML+ si elle stimule la croissance bactérienne et FML- si elle a un effet inhibiteur. Les métabolites connus qui inhibent ou stimulent la FML ne permettent pas toujours d’expliquer cette distinction phénotypique. Dans ce travail de thèse, nous avon développé un workflow multidisciplinaire qui combine l’approche métabolomique non ciblée, l’analyse classique ciblée, les statistiques et les réseaux. L’objectif premier était de dévoiler des métabolites levuriens impliqués dans l’interaction entre levures et bactéries par une comparaison directe des exométabolome des deux phénotypes.À cet effet et pour la première fois dans l’éude d’interactions inter-espèces, la Spectrométrie de Masse à Résonance Cyclotronique des Ions et à Transformée de Fourier (FT-ICR-MS) et la Chromatographie Liquide couplée à la Spectrométrie de Masses (UPLC-Q-TOF-MS) ont été combinées. Pour mieux visualiser les données à haut débit générées par les deux plate-formes, une méthode statistique non supervisée MetICA a été developpée et validée. Par rapport à l’analyse en composantes principales (ACP), cette nouvelle méthode peut réduire la dimension des données d'une façon plus robuste et fiable. Afin d’extraire des métabolites impliquées dans la distinction phénotypique, nous avons comparé différentes methodes de classification et choisi la meilleure pour chaque jeu de données. Les structures putatives de ces biomarqueurs ont été validés par la spectrométrie de masse MS/MS et leurs rôles physiologiques sur la croissance bactérienne ont été confirmées in vitro. La découverte de biomarqueurs a été complétée par l’analyse ciblée réalisées par Chromatographie en Phase Liquide à Haute Performance (HPLC). La complémentarité entre les différentes techniques métabolomiques a conduit à l’identification de nouveaux biomarqueurs de familles distinctes, comme des composés phénoliques, des sucres, des nucléotides, des acides aminés et des peptides. En outre , l'analyse des réseaux métaboliques a révélé des liens entre les biomarqueurs de levure et a suggéré des voies bactériennes influencés par l’exo-métabolome de levure.Notre workflow multidisciplinaire a révélé une réelle capacité à identifier des signatures moléculaires nouvelles et inattendues de l’interaction levure-bactérie
As a complex microbial ecosystem, wine is a particularly interesting model for studying interactions between microorganisms. Contact-independent interactions (indirect interactions) between the yeast Saccharomyces cerevisae and the lactic acid bacterium Oenococcus oeni have a direct effect on malolactic fermentation (MLF), induction and completion, which is an important factor in wine quality. Yeast strains could be classified as MLF+ phenotype if it usually stimulates the bacterial growth or MLF- in the opposite case. The known metabolites that stimulate or inhibit the MLF cannot always explain the phenotypic distinction. In this work, a multidisciplinary workflow combining non-targeted metabolomics, targeted analysis, statistics and network was developed. The main objective was to unravel diverse yeast metabolites involved in yeast-bacteria interaction via a direct comparison of exo-metabolomes of MLF+ and MLF- phenotypes.To that purpose, and for the first time in the research of interspecies microbial interactions, two metabolomics platforms, Fourier Transform Ion Cyclotron Resonance -Mass Spectrometry (FT-ICR-MS) and Liquid Chromatography coupled with Mass Spectrometry (UPLC-Q-TOF-MS) were used in combination. To better visualize the high-throughput data generated from the two platforms, a novel unsupervised statistical method, the MetICA was developed and validated. Compared to classical principal component analysis (PCA), the new method reduced the data dimension in a more robust and reliable way. To extract metabolic features involved in the phenotypic distinction, we have compared different statistical classifiers and selected the best one for each dataset. Putative structures of these biomarkers were validated via MS/MS fragmentation analysis and their physiological roles to bacteria were confirmed in vitro. The discovery of biomarkers was complemented by targeted HPLC (high performance liquid chromatography) analysis. The complementarities between different analytical techniques led to new biomarkers of distinct chemical families, such as phenolic compounds, carbohydrates, nucleotides, amino acids and peptides. Furthermore, metabolic network analysis has revealed connections between yeast biomarkers and suggested bacterial pathways influenced by yeast exo-metabolome.Our multidisciplinary workflow has shown its ability to find new and unexpected molecular evidence of wine yeast-bacteria interaction

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Tose, Lilian Valadares. "Análise de Parafinas por APCI-FT-ICR MS : Uma Análise Rápida e Simples na Identificação de Hidrocarbonetos Saturados, Cíclicos e Poliaromáticos." reponame:Repositório Institucional da UFES, 2014. http://repositorio.ufes.br/handle/10/1348.

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A análise de hidrocarbonetos por técnicas de ionização a pressão atmosférica ou ambiente continua a ser um desafio na espectrometria de massas. Normalmente, a ionização ocorre através de mecanismos de protonação e desprotonação. Para isso, as moléculas de interesse devem apresentar um grupo básico ou ácido que proporcionem a geração de íons [M+H]+ ou [M-H]-. Para superar essa limitação, um método analítico simples, fácil, rápido e poderoso foi desenvolvido com sucesso, adaptado a partir da literatura, para ionizar saturado e insaturado, linear, ramificado, e hidrocarbonetos cíclicos, bem como hidrocarbonetos poliaromáticos e heteroaromáticos presentes em frações de hidrocarbonetos e de misturas de parafina/petróleo bruto utilizando ionização química à pressão atmosférica (APCI), favorecido pela utilização de solventes alifáticos de cadeia curta em um espectrômetro de massas FT-ICR. Entre os reagentes alifáticos estudados, isoctano proporcionou os melhores resultados quando comparado com outros solventes. Além disso, foram estudados outros interferentes do processo de ionização, como concentração da solução injetada e misturas parafina/óleo, que influenciavam desde o perfil dos espectros até as principais classes de compostos identificados. O método torna possível a ionização de hidrocarbonetos pela produção de íons [M -H]+ sem ocorrência de fragmentação.
The analysis of hydrocarbon using atmospheric or ambient ionization techniques still remains a challenge in mass spectrometry. Traditionally, the ionization occurs via protonation or deprotonation. The molecules of interest must have a basic or acidic group to generated [M + H]+ or [M - H]- ions. To overcome such limitation, it is proposed a simple, easy, fast and powerful analytical methodology to ionize saturated (linear and branched), unsaturated, and cyclic hydrocarbons as well as polyaromatic and heteroaromatic hydrocarbonsby atmospheric pressure chemical ionization (APCI) using small hydrocarbons as reagents in a FT-ICR mass spectrometer. These molecules may be present in hydrocarbon fraction samples and paraffin/crude oil blends. Among the APCI hydrocarbon reagents studied, isooctane provided the best results when compared to pentane, hexane, cyclohexane and heptane. The method renders the ionization of hydrocarbons to yield [M – H]+ ions with no associated fragmentation using nitrogen as sheath gas.

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OLIVEIRA, B. G. "Perfil Químico de Manga Ubá (Mangifera indica L.) por Espectrometria de Massas de Altíssima Resolução e Exatidão (FT-ICR-MS)." Universidade Federal do Espírito Santo, 2015. http://repositorio.ufes.br/handle/10/7325.

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Perfil Químico de Manga Ubá (Mangifera indica L.) por Espectrometria de Massas de Altíssima Resolução e Exatidão (FT-ICR-MS)

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TOSE, L. V. "Análise de Parafinas por APCI-FT-ICR MS: Uma Análise Rápida e Simples na Identificação de Hidrocarbonetos Saturados, Cíclicos e Poliaromáticos." Universidade Federal do Espírito Santo, 2014. http://repositorio.ufes.br/handle/10/4722.

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A análise de hidrocarbonetos por técnicas de ionização a pressão atmosférica ou ambiente continua a ser um desafio na espectrometria de massas. Normalmente, a ionização ocorre através de mecanismos de protonação e desprotonação. Para isso, as moléculas de interesse devem apresentar um grupo básico ou ácido que proporcionem a geração de íons [M+H]+ ou [M-H]-. Para superar essa limitação, um método analítico simples, fácil, rápido e poderoso foi desenvolvido com sucesso, adaptado a partir da literatura, para ionizar saturado e insaturado, linear, ramificado, e hidrocarbonetos cíclicos, bem como hidrocarbonetos poliaromáticos e heteroaromáticos presentes em frações de hidrocarbonetos e de misturas de parafina/petróleo bruto utilizando ionização química à pressão atmosférica (APCI), favorecido pela utilização de solventes alifáticos de cadeia curta em um espectrômetro de massas FT-ICR. Entre os reagentes alifáticos estudados, isoctano proporcionou os melhores resultados quando comparado com outros solventes. Além disso, foram estudados outros interferentes do processo de ionização, como concentração da solução injetada e misturas parafina/óleo, que influenciavam desde o perfil dos espectros até as principais classes de compostos identificados. O método torna possível a ionização de hidrocarbonetos pela produção de íons [M - H]+ sem ocorrência de fragmentação.

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Dias, Heloisa Pinto. "Estudo da corrosão naftênica por espectrometria de massas de altíssima resolução e exatidão (ESI –FT-ICR MS) & microscopia de força atômica." reponame:Repositório Institucional da UFES, 2014. http://repositorio.ufes.br/handle/10/1606.

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Capes
Os ácidos naftênicos são considerados os principais responsáveis pela corrosão no processo de refino do petróleo, e se não for devidamente monitorada, a corrosão naftênica pode causar graves prejuízos para a indústria petroquímica. No primeiro capítulo deste trabalho duas amostras de petróleo, tratadas a 300°C/2h e 350°C/6h, foram postas em contato com aço carbono AISI 1020 durante 15 dias. A acidez do óleo original e dos produtos oriundos do tratamento térmico foi monitorada por número de acidez total (NAT), espectrometria de massas de altíssima resolução e exatidão (ESI(-)- FT-ICR) e a corrosão no aço foi monitorada por microsospia de força atômica (AFM). Os dados de ESI(-)-FT-ICR MS mostraram que na classe O2, as principais espécies majoritárias detectadas foram de número de carbono C25-C32 e DBE = 3. Para o tratamento a 350ºC/6h, observou-se uma redução de ~ 80% no NAT. Os resultados obtidos por AFM mostraram que a topografia da superfície do aço exposto ao óleo tratado a 300°C/2h possui efeitos mais pronunciados de corrosão, pois, o padrão de rugosidade medido pela "altura de pico a pico" da superfície, indicou que a superfície exposta ao óleo 300°C/2h, embora apresente uma série de irregularidades é menos pronunciada, que a superfície do aço exposto ao óleo tratado a 350°C/6h. No segundo capítulo, dois petróleos com acidez distinta, J e G, foram caracterizados por ESI (-) - FT-ICR MS. O aço AISI 316 foi analisado por microscopia ótica, microscopia de força atômica e por espectroscopia Raman. Os resultados mostraram que as principais classes identificadas nas amostras foram as classes O2 e N2. Em relação à classe O2, as principais espécies majoritárias detectadas foram de número de carbono C24-C35 e DBE= 3 e C29-C35 e DBE= 4. As imagens de AFM revelaram que para o intervalo de 14 dias, o aço exposto ao óleo J, apresentou fortes alterações topográficas em relação ao branco,caracterizando o início do processo corrosivo. Essas informações são compatíveis com os espectros de Raman, em que para este intervalo de tempo foram evidenciados a formação de Goetita, Magnetita e Hematita. As alterações topográficas para o aço exposto ao petróleo G, só puderam ser observadas após 21 dias de análise por AFM. No terceiro capítulo, uma amostra de petróleo foi tratada termicamente, na presença e ausência de catalisador, a 300 e 350 ºC pelo período de 2, 4 e 6 horas. A acidez do petróleo original e dos produtos oriundos do tratamento térmico com catalisador foi determinada pelo NAT. A variação do conteúdo de polares nas amostras, em especial a classe O2, foi monitorada por ESI (-)-FT-ICR MS. De uma maneira geral, as principais classes identificadas para ambas às amostras foram O2, N e NO2, respectivamente. Em relação à classe O2 correspondente aos ácidos naftênicos, as principais espécies majoritárias foram de C25-C32 e DBE = 4. Observou-se uma redução de 43,50% no petróleo degradado á 350°C durante 4h na presença do catalisador evidenciando assim a eficiência da remoção dos ácidos naftênicos nas condições avaliadas.
Naphthenic acids are considered primarily responsible for corrosion in the oil refining process, and if not properly monitored, the naphthenic corrosion can cause severe damage to the petrochemical industry. In the first chapter of this work, two oil samples treated at 300°C/2h 350°C/6h, were brought in contact with carbon steel AISI 1020 for 15 days. The acidity of the original and products from oil heat treatment was monitored by TAN ESI (-) - FT-ICR-MS and corrosion on steel was monitored by AFM. The ESI (-) - FT-ICR MS showed that the O2 class, the major species detected were majority carbon number of C25-C32 and DBE = 3. For treatment at 350°C/6h, there was a reduction of ~ 80% in the TAN. The results showed that AFM topography of the steel surface exposed to the oil treated at 300°C/2h has higher effects of corrosion, since the pattern of roughness measured by "peak to peak height" of the surface, indicated that the surface exposed to the oil 300°C/ 2h, although it presents a number of irregularities is less pronounced, the surface exposed to the oil-treated steel at 350°C/6h. In the second chapter, two oils with different J and G acidity were characterized by ESI (-) - FT-ICR MS. The AISI 316 steel was analyzed by optical microscopy, atomic force microscopy and Raman spectroscopy. The results showed that the major classes were identified in the samples classes O2 and N2. Regarding O2 class, the major species detected were majority of carbon number C24 and C35 = 3 DBE and DBE and C29-C35 = 4. The AFM images showed that the interval for 14 days, the steel exposed to oil J, showed strong topographic changes from white, characterizing the onset of the corrosion process. This information is consistent with the Raman spectra that for this period of time the formation of goethite, hematite and magnetite were evidenced. Topographical changes to the exposed steel to oil G could only be observed after 21 days of analysis by AFM. The third chapter, a sample oil was thermally treated in the presence and absence of catalyst at 300 and 350 ° C for a period of 2, 4 and 6 hours. The acidity of the original oil and products derived from thermally treated catalyst was determined by TAN. The variation in the content of polar samples, particularly class O2 was monitored by ESI (-) - FT-ICR MS. Generally, the major classes identified for both samples were N, NO2, and O2, respectively. Regarding O2 class corresponding to naphthenic acids, the major species were majority of C25-C32 and DBE = 3. There was a 43.50% reduction in the degraded oil at 350°C for 4h in the presence of the catalyst thus demonstrating the efficiency of removal of naphthenic acids under the conditions evaluated.

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DIAS, H. P. "Estudo da Corrosão naftênica por espectrometria de massas de altíssima resolução e exatidão (ESI-FT-ICR MS) & microscopia de força atômica." Universidade Federal do Espírito Santo, 2014. http://repositorio.ufes.br/handle/10/4721.

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Marchal, Axel. "Recherches sur les bases moléculaires de la saveur sucrée des vins secs : approches analytique et sensorielle." Thesis, Bordeaux 2, 2010. http://www.theses.fr/2010BOR21779/document.

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La saveur sucrée est à l’origine de l’équilibre gustatif des vins secs. On observe uneaugmentation de son intensité au cours de la macération post-fermentaire et de l’élevage enbarrique. Nous montrons que ces phénomènes sont respectivement liés à la libération depeptides de la levure et de composés non-volatils du bois de chêne dans les vins.Le rôle de la protéine Hsp12 de S. cerevisae sur le gain de sucrosité est établi enutilisant des techniques de biologie moléculaire et d’analyse sensorielle.Le développement d’un couplage chromatographie de partage centrifuge –gustatométrie permet de fractionner un extrait de bois de chêne et de purifier plusieurscomposés sapides. L’utilisation de la LC-FT/MS et de la RMN nous a permis d’identifierquatre nouvelles molécules, appelées quercotriterpénosides (QTT), deux d’entre elles (QTTI et III) possédant une saveur douce. Les seuils de perception du QTT I et d’un lignane amer,le lyonirésinol, sont respectivement 590 μg/L et 1.52 mg/L.La mise au point d’une méthode de quantification de ces composés en LC-FT/MS nous apermis de démontrer l’impact organoleptique du lyonirésinol dans les vins.Il est probable que les QTT I et III contribuent, directement ou indirectement, au gain desucrosité conféré par le bois de chêne
Sweetness contributes to the balance in taste of dry wines. An increase in sweet taste isobservable during post-fermentation maceration and oak-barrel aging. We have revealed thatthese phenomena are respectively due to the release in wines of yeast peptides and nonvolatileoak wood compounds.The role of Hsp12 protein from S.cerevisae on the increase in sweetness is establishedwith both molecular biology and sensorial analysis techniques.The development of a method coupling centrifugal partition chromatography andgustatometry has enabled us to fractionate an oak-wood extract and to purify several sapidcompounds. Thanks to both the LC-FTMS and the NMR spectroscopy methods, we havehighlighted four new molecules, called quercotriterpenosides (QTT), out of which QTT Iand III are responsible for a sweet taste. The perception thresholds of QTT I and a bitterlignan, lyoniresinol, are respectively 590 μg/L and 1.52 mg/L.LC-FT/MS method has been used to develop a quantification method for these compoundsand we have demonstrated the organoleptic impact of lyoniresinol in wines.QTT I and III are likely to contribute, directly or indirectly, to the increase in sweetnessconsecutive to barrel aging in dry wines

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Zhang, Haizhen. "Characterization of Cucurbituril Complex Ions in the Gas Phase Using Electrospray Ionization Fourier Transform Ion Cyclotron Resonance Mass Spectrometry." Diss., CLICK HERE for online access, 2006. http://contentdm.lib.byu.edu/ETD/image/etd1582.pdf.

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Magalhães, Ilídio Miguel Teixeira. "Proteome of biofilm produced by a S. pseudintermedius strain." Master's thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/14291.

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Mestrado em Bioquímica
Staphylococcus pseudintermedius is an opportunistic pathogenic bacterium responsible for most skin and post-surgical infections in dogs. The number of bacterial strains resistant to β-lactam antibiotics is increasing and are the major challenges now faced by veterinary medicine. Bacteria that produce biofilm are more resistant to treatment and thus, the production of this structure is already considered a virulence factor. In a biofilm, bacteria are embedded in a matrix of extracellular polymeric substances (EPS) some of which are proteins. With the objective to know more of this array element, the characterization of the biofilm matrix proteome (BMP) from a highly virulent S. pseudintermedius strain isolated from a dog with severe pyoderma was performed. Biofilm was developed by culturing the S. pseudintermedius strain 5819/10 in specific media. The biofilm matrix was then be separated from bacterial cells and evaluated for their protein content and complexity. Finally, the proteome was separated by 1D electrophoresis and characterized by nanoLC-ESI-Q-TOF and analysed using bioinformatics tools. The BMP of strain S. pseudintermedius 5819/10 consisted in a diverse group of proteins, where 63% of the proteins could be related to either the extracellular region or the plasma membrane, as protein complexes, and most of them had functions essential to cell survival. However, it was not possible to establish a clear relation between them and biofilm formation. Proteins known to be involved in biofilm formation consisted mostly of regulator factors of biofilm formation as well as virulence factors of-mainly-bacterial cell adhesion and host colonization. The prevalence of adhesins and the almost total absence of proteins involved in EPS synthesis pointed to a biofilm matrix where cells are directly or indirectly closely glued together to each other.
Staphylococcus pseudintermedius (S.pseudintermedius) é uma bactéria patogénica oportunista, responsável pela maioria das infeções cutâneas e pós-cirúrgicas em cães. O número de estirpes resistentes a antibióticos β-lactâmicos está a aumentar constituindo actualmente um dos grandes desafios enfrentados pela medicina veterinária. As bactérias mais resistentes ao tratamento são aquelas que produzem biofilme sendo esta capacidade considerada um fator de virulência. Num biofilme, as bactérias estão envoltas numa matriz de substâncias poliméricas extracelulares (SPE), algumas das quais são proteínas. Tendo por objectivo obter mais informação acerca do biofilme, foi caracterizado o proteoma da matriz do biofilme de uma estirpe bastante virulenta de S. pseudintermedius isolada de um cão com piodermite profunda. Para tal cultivaram-se biofilmes da estirpe de S. pseudintermedius 5819/10 em meio apropriado, separou-se a matriz das suas células bacterianas e avaliou-se as proteínas presentes quanto ao seu conteúdo e complexidade. Posteriormente o proteoma foi separado por electroforese 1D, caracterizado por nanoLC-ESI-Q-TOF e analisado usando ferramentas bioinformáticas Constatou-se que o proteoma da matriz do biofilme da estirpe 5819/10 de S. pseudintermedius é muito diverso e que 63% das proteinas podem estar relacionadas com a região extracelular do biofilme ou da membrana plasmática na forma de complexos proteicos. Verificou-se também que a maioria das proteínas identificadas possui funções essenciais para a sobrevivência da bactéria mas não foi possível estabelecer uma relação clara entre elas e a formação de biofilmes. Algumas proteínas que se sabe estarem envolvidas na formação de biofilmes foram identificadas, tratam-se principalmente de factores reguladores da formação de biofilme e outros factores de virulência relacionados com a colonização de um hospedeiro a adesão bacteriana a uma superfície. A prevalência de adesinas e a ausência quase total de proteínas envolvidas na síntese de SPEs, forneceu dados que apoiam a hipótese que a matriz do biofilme do S. pseudintermedius 5819/10 seja constituída por células directamente ou indirectamente unidas entre si.

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Reeves, Savanah Gail. "Condensed tannin characterization with FT-ICR MALDI mass spectrometry and separation with saw-tooth gradient HPLC." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami1591185101154831.

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Faria, Maria Juíva Marques de. "Oleorresina de Copaifera spp.: caracterização, verificação da atividade antimicrobiana in vitro e avaliação preliminar de uma formulação em vacas leiteiras com mastite." Universidade Federal de Goiás, 2014. http://repositorio.bc.ufg.br/tede/handle/tede/3939.

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Bovine mastitis is an inflammatory/infectious process of the mammary gland, its etiology is complex and multivariate. The most common mastitis has bacterial origin. Because of the high cost to treat this disease, and the bacterial resistance to antibiotics, beyond the losses due to the milk discard or the presence of drug residues in milk, studies are necessary to find out alternative methods to circumvent these problematic. The medicinal plants with antimicrobial activity have been making room in veterinary medicine with the objective to reduce the impact and the use of drugs indiscriminately, as well as maintain the integrity of the animal and control the dissemination of resistant bacterial lineage. Therefore, the aim of this work was characterize the oleoresin Copaifera spp., verify the antimicrobial activity in vitro of oleoresin and essential oil of Copaifera spp. in combating against aerobic and facultative isolated bacteria from cows’ milk with subclinical grade III mastitis diagnostic and evaluate preliminarily, in vivo, phytotherapic formulation composed of Copaifera spp. The tests for characterization of the oleoresin, confirmed its authenticity and quality, considered appropriate for use. The analyzes performed by gas chromatography coupled to mass spectrometry (GC/MS) and electrospray ionization Fourier transformed íonic cyclotron resonance mass spectrometry (ESI FT-ICR MS) identified sesquiterpenes and diterpenes present in the essential oil and oleoresin of Copaifera spp., respectively. The technique of High Performance Liquid Chromatography (HPLC) for sesquiterpenes, especially for β-caryophyllene, can be used in quality control of essential oil and oleoresin of Copaifera spp., as well as in phytotherapic formulation using oleoresin of Copaifera spp. The oleoresin showed better antimicrobial activity than the essential oil of Copaifera spp. (ρ<0,0001) in combating the 55 isolated bacteria. The antibiogram test of the three phytotherapic formulations demonstrated that the oleoresin had antimicrobial activity against the isolated microorganisms. The preliminary evaluation, in vivo, of a phytotherapic formulation containing 20% oleoresin of copaiba was neither effective nor safe, because it intensified the inflammatory process, requiring further tests, such as cytotoxicity and irritability of the raw material plant and of the vehicle used. Key words: Bovine Mastitis. Oleoresin. Essential Oil. Copaifera spp. Minimum Inhibitory Concentration. ESI FT-ICR MS.
Mastite bovina é um processo inflamatório/infeccioso da glândula mamária, de etiologia complexa e multivariada, sendo a de origem bacteriana a mais frequente. Devido aos elevados custos dos tratamentos dessa enfermidade, resistência bacteriana aos antibióticos, além dos prejuízos inerentes ao descarte do leite ou à presença de resíduos de medicamentos no mesmo, faz-se necessário estudos que busquem métodos alternativos para contornar essa problemática. As plantas medicinais com potencial antimicrobiano vêm ganhando espaço na medicina veterinária com o objetivo de reduzir o impacto e o uso de medicamentos de forma indiscriminada, bem como manter a integridade do animal e controlar a disseminação de linhagens bacterianas resistentes. Diante disso, o objetivo desse trabalho foi caracterizar a oleorresina de Copaifera spp., verificar atividade antimicrobiana in vitro da oleorresina e do óleo essencial de Copaifera spp. frente às bactérias aeróbias e facultativas isoladas de leite de vacas diagnosticadas com mastite subclínica grau III e avaliar preliminarmente, in vivo, formulação fitoterápica à base de Copaifera spp. Os testes de caracterização da oleorresina de Copaifera spp. demonstraram sua autenticidade e qualidade, a qual foi considerada adequada para o uso. As análises realizadas por cromatografia gasosa acoplada à espectrometria de massas (CG/EM) e por espectrometria de massas com ionização por electrospray de ressonância ciclotrônica de íons por transformada de Fourier (ESI FT-ICR MS) identificaram os sesquiterpenos e diterpenos presentes no óleo essencial e na oleorresina de Copaifera spp., respectivamente. A técnica Cromatografia Líquida de Alta Eficiência (CLAE) para sesquiterpenos, em especial para β-cariofileno, pode ser utilizada no controle de qualidade de oleorresina e óleo essencial de Copaifera spp., bem como em formulação fitoterápica utilizando oleorresina de Copaifera spp. como matéria-prima vegetal. A oleorresina apresentou melhor atividade antimicrobiana do que o óleo essencial de Copaifera spp. (ρ<0,0001) frente às 55 bactérias isoladas. O teste de antibiograma das três formulações fitoterápicas demonstrou que a oleorresina de copaíba reproduziu a sua atividade antimicrobiana frente aos micro-organismos isolados. A avaliação preliminar, in vivo, de uma formulação fitoterápica contendo 20% oleorresina de copaíba não foi eficaz e nem segura, pois intensificou o processo inflamatório, havendo necessidade de testes futuros, como de citotoxicidade e de irritabilidade dessa matéria-prima vegetal e do veículo utilizado.

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Bell, Nicholle Georgina Anneke. "Molecular-scale characterisation of humic substances using isotope-filtered nD NMR spectroscopy." Thesis, University of Edinburgh, 2016. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.716584.

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Humic substances (HS), the complex mixture of organic molecules produced by microbial and abiotic degradation of plant and animals residues, are the major components of organic matter in soil and natural waters. As such, they are vital to the integrity of soil, play important roles in nutrient biogeochemical cycling and determine the mobility and fate of both nutrients and contaminants. How HS enact their varied roles, however, is largely unknown due to the lack of comprehension of their molecular make-up. What is known is that they contain aromatic (e.g. phenols, condensed aromatics) and aliphatic (e.g. carbohydrates, lipids) molecules with prevailing carboxyl and hydroxyl functionalities. As for other complex chromatographically inseparable mixtures, high-resolution analytical techniques such as Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) as well as Nuclear Magnetic Resonance (NMR) spectroscopy have been applied to study HS composition at the molecular level. While FT-ICR MS can provide molecular formulae, it is only NMR that can unveil structures. Until now, however, very few unambiguous structures of individual molecules have emerged from standard NMR experiments. This is because purposely designed multidimensional NMR experiments are required to achieve ‘spectroscopic separation’ where chromatography fails. In this work, ‘spectroscopic separation’ was accomplished with the aid of chemical modification in the form of 13C methylation of COOH and OH groups. 13C containing tags allow the observation of signals only from molecules carrying these tags. In combination with purposelydesigned isotope-filtered NMR experiments, these tags act as spies reporting on their surrounding structure. This is achieved by utilising scalar and dipolar couplings to transfer the polarisation between protons and carbons of the 13CH3O groups and nuclei of the parent molecules. The necessary spectral resolution is attained using 3D/4D NMR experiments. This approach provides access to an array of correlated chemical shifts of HS molecules and represents a paradigm shift in the use of tags in investigations of complex mixtures: instead of focusing only on the tags, they are used to obtain structural information from the molecules they are attached to. The compounds at the centre of this investigation are the phenols of HS. These molecules are thought to be important in many of the key processes in organic matter rich soils, particularly peat. For example, their accumulation is thought to impair the activity of extracellular enzymes essential for the degradation of peat HS. Understanding the nature and source of phenols would provide a more fundamental framework for rationalising their role in peat, as well as other carbon rich soils. The developed methodology was initially tested on model mixtures containing 3 or 9 phenolic compounds before applying it to a operational fraction of HS, fulvic acid, extracted from a Scottish raised peat bog. For this fulvic acid, over 30 major phenolic molecules/moieties were identified, many of which can be directly traced to the flora prevalent in the vicinity of the sampling site. For the first time in 150 years of HS research, a novel analytical methodology has yielded unambiguous structural information, providing the first steps towards understanding the various roles of HS in natural systems.

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46

Adilbekov, Dauren. "Analytical analysis of Roman amphorae." Master's thesis, Universidade de Évora, 2016. http://hdl.handle.net/10174/20851.

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Abstract: The analysis of organic residues present in ancient pottery can give important information for archaeologists. Diets, habits, technologies and original use of the vessels can be identified through this studies. Fourier transform infrared spectroscopy (FT–IR) and gas chromatography coupled with mass spectrometry (GC–MS) were used in order to analyse organic resinous materials from the interior surfaces of Roman amphorae belonging to the archaeological collection of DRASSM and Museum of Arles Antique. In addition, wine amphorae from Grand Congloué 2 shipwreck were analysed. The FTIR spectra obtained by the technique of KBr micropellets, prepared directly with the materials scraped from the amphora without any further sample preparation, provided enough information to establish their diterpenoic nature. GC–MS enabled to identify dehydroabietic acid, 7-oxodehydroabietic acid, 7-hydroxy-dehydroabietic acid, 15-hydroxy-7-oxodehydroabietic acid, methyl dehydroabietate, retene. The presence of diterpenoids and retene provided evidence that the amphorae examined were waterproofed with a pitch produced from resinous wood of plants from the Pinaceae family or mainly consist of Coniferae species. Moreover presence of retene in samples indicates that pitch was heated. Wine and fish amphorae were studied. Some fish amphorae samples did not show the presence of pitch in GC-MS analyses. This work studies for the first time pitch of an fish amphorae in the laboratory of IMBE.

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Lovascio, Sara. "Cold Plasma deposition of organosilicon films with different monomers in a dielectric-barrier discharge." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2010. http://tel.archives-ouvertes.fr/tel-00815260.

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Cette thèse porte sur une étude fondamentale sur le dépôt des couches minces d'organosiliciés par des Décharges à Barrière Diélectrique (DBD), un procédé très intéressant pour l'application aux textiles. La plupart des dépôts des couches d'oxyde de silicium sont déposées à partir du précurseur hexaméthyle silixone (HMDSO).De plus très peu d'études sont consacrées aux mécanismes de dépôt des couches à la pression atmosphérique. Dans cette étude les propriétés des couches minces déposées par DBD alimentées par Ar/HMDSO/O2, Ar/PMDSO (pentaméthyldisiloxane)/O2 et Ar/TMDSO (tetraméthyldisiloxane)/O2, avec différentes proportions de l'oxygène, ont été confrontées aux analyses, par GC-MS, des gaz sortant du réacteur. Nous avons trouvé que l'ajout d'O2 au gaz d'alimentation n'améliore pas l'activation du précurseur organosilicié, même s'il augmente la puissance injectée. En revanche il influence fortement la composition chimique des dépôts et favorise une forte réduction de la concentration des sous-produits dans le gaz sortant du réacteur. Sans ajout de l'O2, des couches minces obtenues contiennent beaucoup de carbone , avec rétention de la structure du précurseur de départ. En réduisant le nombre de -CH3 dans le précurseur (HMDSO>PMDSO>TMDSO), le nombre et l'abondance des sous-produits détectés dans le gaz sortant du réacteur diminuent fortement. Il semblerait que les unités de répétition diméthylsiloxane et hydrométhylsiloxane jouent un rôle important dans l'oligomérisation des trois précurseurs. Différents mécanismes d'activation, ainsi que différents procédés de formation des groupes Si-OH dans les dépôts, ont été proposés pour les trois précurseurs.

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48

Vera, Carrasco Luciano. "Sensory quality control of alcoholic beverages using fast chemical sensors." Doctoral thesis, Universitat Rovira i Virgili, 2010. http://hdl.handle.net/10803/9061.

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Control de calidad sensorial de bebidas alcohólicas utilizando rápidos sensores químicos
En la presente tesis Doctoral, han sido aplicados dos sensores artificiales para el análisis de
bebidas alcohólicas: la nariz electrónica basada en la espectrometría de masas (MS) y la lengua
electrónica basada en la espectroscopía infrarroja con transformada de Fourier (FTIR). El
propósito fue desarrollar nuevas estrategias para analizar la autenticidad de estos productos,
desde un punto de vista sensorial, por medio de técnicas las espectrales antes mencionadas.
Adicionalmente, ha sido utilizado un espectrofotómetro UV-visible como ojo electrónico. El
trabajo presentado pretende ser un avance significativo hacia el desarrollo de un catador
electrónico mediante la fusión de los tres sensores químicos: nariz electrónica, lengua
electrónica y ojo electrónico.
Sensory quality control of alcoholic beverages using fast chemical sensors
In the present Doctoral Thesis, two chemical artificial sensors are applied to the analysis of
alcoholic beverages: the Mass Spectrometry (MS)-based electronic-noses and Fourier
transform infrared (FTIR)-based electronic-tongue. The aim was developing new strategies to
test the authenticity of these products, from a sensory point of view, by means of the spectral
techniques above mentioned. Additionally, has been used an UV-visible spectrophotometer as
electronic eye. The work presented wants to be a significant advance towards the development
of an electronic taster through the fusion of three chemical sensors: electronic nose, electronic
tongue and electronic eye.

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49

Östman, Ninnie. "Undersökning av avgasemissioner till vatten från dieselinombordsmotorer i fritidsbåtar : En jämförande studie av olika bränslen." Thesis, Uppsala University, Department of Earth Sciences, 2006. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9280.

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In this Masters Thesis emissions to water from diesel engines in pleasure boats when driven with alternative fuels have been investigated. Two alternative fuels, Fischer-Tropsch-diesel (FT-diesel) and a blend of FT-diesel and rapeseed methyl ester (RME) have been compared with diesel of Swedish environmental class 1 (diesel EC1). The alternative fuels have been compared using two older marine diesel engines, and water samples have been taken from the water in the exhaust system before the exhaust compounds reaches the recipient. The water samples have been analysed with gas chromatography (GC) and mass spectrometry (GC/MS), to analyse volatile and semi volatile compounds including aldehydes and ketons. To investigate the acute toxicity of the exhaust water a 24 h ecotoxicological test was preformed with the crustacean Artemia fransiscana.

The results showed considerable differences in emissions of poly aromatic hydrocarbons (PAHs) and alkylated benzenes. From diesel EC1, the amounts of PAHs and alkylated benzenes were significantly higher than from pure FT-diesel and FT-diesel containing 20 % of RME. Pure FT-diesel generated the lowest amounts of PAH and alkylated benzenes. The FT-diesel containing 20 % RME generated higher amounts of benzene than diesel EC1. FT-diesel and FT-diesel with a 20 % blend of RME generated the same amount of acetone, which in turn was higher than the concentration of acetone in the exhaust water, using diesel EC1. Based on the analysis, FT-diesel is the best alternative from an exhaust emission point-of-view, concerning both the amounts and the difference in chemical composition of the combustion products released into the water.

The ecotoxicological test showed no effect on the test organism using either of the samples.

Fritidsbåtsintresset är stort i Sverige och båtlivet betyder mycket för många svenskar. Tyvärr är användningen av fritidsbåtar förknippad med en rad miljöproblem. Avgasutsläpp till vatten och luft från fritidsbåtsmotorer påverkar den lokala miljön avsevärt. Gammal teknik med dålig förbränning används fortfarande i stor utsträckning. På kort sikt, innan den gamla tekniken är utbytt, är det viktigt att den äldre motorparken använder miljöanpassade bränslen för att utsläppen till sjöar och hav ska bli så skonsamma som möjligt. Det är dock viktigt att utvärdera miljöpåverkan av dessa alternativa bränslen, så att det verkligen är ett bättre alternativ ur miljösynpunkt.

I detta examensarbete har utsläpp till vatten från dieselinombordsmotorer vid drift med olika bränslen undersökts. Två miljöanpassade dieselbränslen; FT-diesel (Fischer-Tropsch) och en procentinblandning av rapsmetylester (RME) i FT-diesel, har jämförts med diesel av svensk miljöklass 1 (MK1). Bränslena har testkörts i två äldre, marina dieselmotorer och prover har tagits på det avgasblandade kylvattnet innan det når recipienten. Det avgasblandade kylvattnet har analyserats med avseende på delvis flyktiga och flyktiga föreningar, aldehyder samt ketoner. Analyserna har skett med gaskromatografi och masspektormetri (GC/MS-screening) på externt laboratorium. För att testa avgasvattnets akuta giftighet har även ett akut (24h) ekotoxikologiskt test utförts på kräftdjuret Artemia fransiscana.

Analysresultatet visade skillnad i utsläpp av polyaromatiska kolväten (PAH) och alkylbensener. Vid körning med diesel MK1 genererades betydligt högre halter av PAH:er och alkylbensener, än vid körning med FT-diesel och FT-diesel med 20 % inblandning av RME. Ren FT-diesel gav de lägsta halterna av PAH:er och alkylbensener.

Utsläppshalterna av bensen uppvisade inte lika stor skillnad mellan de olika bränslena. Blandningen FT-diesel med 20 % RME gav lite högre halter bensen än vad diesel MK1 gjorde. Ren FT-diesel uppvisade lägst halt bensen. Utsläpp av aceton visade sig vara lika för FT-diesel och FT-diesel med 20 % RME och gav högre halter än vad diesel MK1 gjorde. Baserat på analysresultaten är FT-diesel det bästa bränslet ur emissionssynpunkt med avseende på vilka ämnen som hamnar i vattenfasen.

Det ekotoxikologiska testet visade ingen skillnad mellan de olika bränslena. Avgasvatten från bränslena hade inte någon akut toxisk effekt på testdjuret.

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50

Kim, Dong Hyun. "Investigation of HIV anti-viral drug effect on HPV16 E6 expressing cervical carcinoma cells using advanced metabolomics methods." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-hiv-antiviral-drug-effect-on-hpv16-e6-expressing-cervical-carcinoma-cells-using-advanced-metabolomics-methods(d52b3b66-2a7b-4577-a334-b74bc12b27cc).html.

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Metabolomics approaches have recently been used to understand the complex molecular interactions of biological systems. One popular area in which these methods are being developed is to understand the biochemical changes during abiotic and biotic stresses; for example, how a cell may respond to a drug. Since metabolites are the end products of gene expression, these can be used to indicate the result of the activities and interaction of the cell or organism with its environment. The investigation of the level and compositional changes of metabolites against metabolic stresses such as chemotherapeutic treatment (drug exposure) are required to understand more fully abiotic perturbation to biological systems. The aim of this project was to understand the metabolic effect that the anti-viral drugs indinavir and lopinavir (currently used by HIV patients) have on HPV-related cervical cancer cell lines by measuring changes in metabolism using a wide range of analytical techniques; including Fourier transform infrared (FT-IR) and Raman spectroscopies, and gas and liquid chromatography-mass spectrometry (GC and LC-MS). The analyses and interpretation of the large volumes of complex multidimensional data generated by metabolomics approaches were performed with a combination of multivariate data analysis techniques such as principal components analysis (PCA) and canonical variates analysis (CVA), as well as univariate approaches such as N-Way analysis of variance (ANOVA). By combining biochemical imaging, metabolite fingerprinting and footprinting, and metabolite profiling, with multi- and uni-variate analyses, the actions and effects of the anti-viral drugs were investigated. FT-IR spectroscopy was initially used to generate global biochemical finger- and foot-prints, and Raman spectroscopy was employed to investigate intracellular distribution of metabolites, and other cellular species, as well as the localisation of drug molecules within cells. FT-IR spectroscopy ascertained that the intra- and extra-cellular metabolomes were being directly influenced in a fashion that correlated with increasing anti-viral dosing; these effects were phenotypic rather than measurements of the drug level. Raman imaging spectroscopy indicated that the indinavir but not lopinavir was being compartmentalised within the cell nucleus, but only in HPV early protein 6 (E6) expressing cells. This observation was further confirmed by fractionation of cell samples into nuclear and cytoplasmic fractions and assessing the indinavir concentrations via LC-MS. Finally, LC-MS and GC-MS metabolite profiling were employed to investigate changes in the intracellular metabolome in response to the anti-viral compounds across a range of physiologically relevant concentrations and in the presence and absence of the E6 oncoprotein. General effects of both anti-viral compounds included the regulation of metabolites such as glutathione, octenedionoic and octadecenoic acids, which may be involved in stress related responses, reduced levels of sugars and sugar-phosphates indicating a potential arrest of glycolysis, and reduced levels of malic acid indicating potential decreased flux into the TCA cycle; all indicating that central metabolism was being reduced. Finally, LC-MS based quantification indicated that in the presence of E6, lopinavir was actively removed from the cell, whereas the indinavir intracellular concentration increased concomitantly with the level of dosing. These investigations have revealed that metabolomics approaches are an apt tool for the study of anti-viral effects within cell cultures, but improvements need to be made with respect to the major limitation of metabolite identification.

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Dissertations / Theses on the topic 'NanoLC FT MS/MS'

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