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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Desenvolvimento de metodologia para separação de carboidratos predominantes em alimentos por eletroforese capilar / Method development for the separation of carbohydrates predominant in foods by capillary electrophoresis

Meinhart, Adriana Dillenburg 16 August 2018 (has links)
Orientadores: Helena Teixeira Godoy, Roy Edward Bruns / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Alimentos / Made available in DSpace on 2018-08-16T15:04:06Z (GMT). No. of bitstreams: 1 Meinhart_AdrianaDillenburg_D.pdf: 1252628 bytes, checksum: b7a02daccb3ff84e9c4321162440ec4f (MD5) Previous issue date: 2010 / Resumo: Os carboidratos são compostos muito abundantes na natureza. Estão presentes em todas as etapas evolutivas, tanto em vegetais como animais. Quaisquer reações, de anabolismo ou catabolismo envolvem, de alguma forma, algum carboidrato. Na indústria alimentícia são responsáveis por diversos fenômenos que promovem efeitos químicos, físicos e sensoriais nos alimentos. A importância destes compostos acompanha etapas que vão desde a obtenção da matéria-prima, a formulação, o processamento, as características do produto final até o tratamento dos resíduos gerados. São compostos de ações biológicas e tecnológicas distintas, mas de características físico-químicas semelhantes e, por isso, de difícil separação. Diversos métodos já foram desenvolvidos para a análise desses compostos. No entanto, dentre a literatura pesquisada, nenhum método investigou a possibilidade de separação simultânea dos 13 carboidratos geralmente encontrados em alimentos: glicose, frutose, sacarose, lactose, galactose, lactulose, epilactose, arabinose, manose, maltose, xilose, ribose e maltotriose. Nesse estudo, foram avaliados os efeitos de três diferentes metodologias na separação desses compostos, envolvendo eletroforese capilar de zona, cromatografia eletrocinética micelar com tensoativo catiônico e tensoativo aniônico. Foram investigados diversos fatores que possam influenciar na separação, dentre eles, o tipo e a concentração do eletrólito, o pH, a concentração de surfactante, a voltagem, temperatura, adição de outros sais como tetraborato de sódio, fosfato de sódio, acetato de sódio e cloreto de sódio e a adição de solventes orgânicos como etanol e acetonitrila. Foram utilizadas técnicas estatísticas multivariadas para a otimização do pH, da concentração do eletrólito e do tensoativo. Através da função de Derringer e Suich foi possível realizar a avaliação simultânea de várias respostas e prever as condições analíticas das metodologias de separação. Utilizando a eletroforese capilar de zona foi possível obter a separação de 8 compostos, por cromatografia eletrocinética micelar contendo surfactante catiônico foi possível separar 9 compostos (sacarose, lactose, lactulose, glicose, arabinose, manose, frutose, xilose e ribose), enquanto que utilizando tensoativo aniônico foi obtida a separação dos 13 compostos. Os métodos estatísticos multivariados se apresentaram como uma valiosa ferramenta para o tratamento dos dados e a predição matemática das condições ótimas de separação. Além disso, permitiram a redução do número de experimentos aliada a obtenção de um grande número de informações a respeito dos sistemas estudados / Abstract: The carbohydrates are compounds very abundant in nature. They are present in all evolutionary steps, both in vegetables and animals. Any metabolism or synthesis reaction involves, in some way, a carbohydrate. In food industries, carbohydrates are compounds responsible for several phenomena that promote chemical, physical and sensorial effects. These compounds are important in raw material obtention, formulation, processing, final product characteristics and generated residue treatment. They are compounds having different biological and technological actions, but with similar physico-chemical characteristics and, for this reason, are hard of separate. Several methods have been developed for the analysis of these compounds. However, in the research literature, no method investigating the possibility of simultaneous separation of the 13 carbohydrates commonly found in foods: glucose, fructose, sucrose, lactose, galactose, lactulose, epilactose, arabinose, mannose, maltose, xylose, ribose and maltotriose was found. In this work, three different methodologies for the separation of these compounds were evaluated, involving capillary zone electrophoresis, micellar electrokinetic chromatography with cationic and anionic surfactants. Several factors that could influence the separation were assayed, electrolyte type and concentration, voltage, temperature, addition of sodium tetraborate, sodium phosphate, sodium acetate and sodium chloride salts and addition of organic solvents like ethanol and acetonitrile. Multivariate statistical techniques were used to optimize pH and electrolyte and surfactant concentrations. Employing the Derringer and Suich desirability function it was possible to make a simultaneous evaluation of several responses and predict the optimum analytical conditions of separation. Using the method of capillary zone electrophoresis it was possible to obtain the separation of 8 compounds, by micellar electrokinetic chromatography containing cationic surfactant. It was possible to separate 9 compounds (sucrose, lactose, lactulose, glucose, arabinose, mannose, fructose, xylose and ribose), when using an anionic surfactant. it was obtained the 13 compounds separation. The multivariate statistical methods were a valuable tool for data treatment and for mathematical prediction of the optimum separation conditions. Moreover, they allowed a reduction in number of experiments as well as the obtention of a great amount of information concerning the studied systems / Doutorado / Doutor em Ciência de Alimentos
2

Identification of Monoclonal Antibodies:Peptide Mass Fingerprinting (PMF) with Matrix Assisted Laser Desorption/Ionization (MALDI), Time of Flight (ToF), Mass Spectrometry (MS) and Protein Peptide Mapping (PPM) with Capillary Electrophoresis (CE) / Identifiering av monoklonala antikroppar:Peptide Mass Fingerprinting (PMF) med Matrix Assisted Laser Desorption/Ionization (MALDI), Time of Flight (ToF), Masspektrometri (MS) och Protein Peptide Mapping (PPM) med kapillärelektrofores (CE)

Bengtsson, Sofia January 2023 (has links)
Antalet monoklonala antikroppar som används i läkemedel ökar kraftigt. Dessa läkemedel är dyra och risken för förfalskning är stor. Behovet att utveckla en metod för snabb och precis identifiering av monoklonala antikroppar är därför brådskande. För identifiering utfördes analyser med Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-ToF-MS), Capillary Gel Electrophoresis (CGE) and Capillary Zone Electrophoresis (CZE) på nio monoklonala antikroppar. Fokuset var att undersöka huruvida signifikanta fysiokemiska egenskaper och unika aminosyrasekvenser var närvarande och kunde urskiljas. Olika analyser med MALDI-ToF-MS användes till att både separera de monoklonala antikropparna baserat på dess fysiokemiska egenskaper, och annotera aminosyrasekvenser innehållande nyckelfragment. Med metoderna baserade på kapillärelektrofores uppnåddes också separation. CZE föredras framför CGE då mängden data som erhålls från CZE är större och provberedningen är enklare. Sammanfattningsvis utformades ett protokoll för identifieringsprocessen, vilket inleds med MALDI-ToF-MS-analyser av monoklonala antikroppar på reducerad form mot kända referenser. Därefter är en hypotes formulerad utifrån vilka antikroppar som ser mest lika ut. Slutligen analyseras dessa med CZE för fastställning av den monoklonala antikroppens identitet. / The number of monoclonal antibodies used in pharmaceuticals is increasing sharply. These medicines are expensive, and the risk of counterfeiting is high. The need to develop a method for rapid and precise identification of monoclonal antibodies is therefore urgent. For identification, analyses were performed with Matrix Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-ToF-MS), Capillary Gel Electrophoresis (CGE) and Capillary Zone Electrophoresis (CZE) on nine monoclonal antibodies. The focus was to investigate whether significant physiochemical features and unique amino acid sequences were present and could be distinguished. Various analyses with MALDI-ToF-MS were used to both separate the monoclonal antibodies based on their physicochemical properties and annotate amino acid sequences containing key fragments. With the methods based on capillary electrophoresis, separation was also achieved. CZE is preferred over CGE as the amount of data obtained from CZE is greater and sample preparation is simpler. In summary, an identification process protocol was designed and is initiated with MALDI-ToF-MS analyses of reduced-form monoclonal antibodies against known references. A hypothesis is then formulated based on which antibodies look the most similar. Finally, these are analysed by CZE to determine the identity of the monoclonal antibody.

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