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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

A Computational Study of the Effects of Heterogeneities on the Estimation of Mechanical Properties of Biological Samples

Nagle, Aditee P. 27 September 2005 (has links)
No description available.
2

Custom Device for Low-Dose Gamma Irradiation of Biological Samples

Bi, Ruoming 2011 December 1900 (has links)
When astronauts travel in space, their primary health hazards are high-energy cosmic radiations from galactic cosmic rays (GCR). Most galactic cosmic rays have energies between 100 MeV and 10 GeV. For occupants inside of a space shuttle, the structural material is efficient to absorb most of the cosmic-ray energy and reduce the interior dose rate to below 1.2 mGy per day. However, the biological effects of prolonged exposure to low-dose radiation are not well understood. The purpose of this research was to examine the feasibility of constructing a low-dose irradiation facility to simulate the uniform radiation field that exists in space. In this research, we used a pre-manufactured incubator, specifically the Thermo Scientific Forma Series II Water Jacketed CO2 Incubator, to act as shielding and simulate the exterior of the space shuttle. To achieve the desired dose rate (< 1 mGy/h) inside the incubator volume, the computer code MCNPX was used to determine required source activity and distance between the shielding and source. Once the activity and distance were calculated, an experiment was carried out to confirm the simulation results. The confirmation used survey meters and thermoluminescence dosimeters (TLDs) to map the radiation field within the incubator.
3

A Capillary-Based Microfluidic System for Immunoaffinity Separations in Biological Matrices

Peoples, Michael 01 January 2008 (has links)
The analysis of biological samples in clinical or research settings often requires measurement of analytes from complex and limited matrices. Immunoaffinity separations in miniaturized formats offer selective isolation of target analytes with minimal reagent consumption and reduced analysis times. A prototype capillary-based microfluidic system has been developed for immunoaffinity separations in biological matrices with laser-induced fluorescence detection of labeled antigens or antibodies. The laboratory-constructed device was assembled from two micro syringe pumps, a microchip mixer, a micro-injector, a diode laser with fused-silica capillary flow cell, and a separation capillary column. The columns were prepared from polymer tubing and packed under negative pressure with a stationary phase that consisted of biotinylated antibodies attached to streptavidin-silica beads. A custom software program controlled the syringe pumps to perform step gradient elution and collected the signal as chromatograms. The system performance was evaluated with flow accuracy, mixer proportioning, pH gradient generation, and assessment of detectability. A direct labeling/direct capture immunoaffinity separation of C-reactive protein (CRP) was demonstrated in simulated serum. CRP, a biomarker of inflammation and cardiovascular disease risk assessment, was fluorescently labeled in a one-step reaction and directly injected into the system. A quadratic calibration model was selected and precision and accuracy were reported. Parathyroid hormone was also analyzed by the direct capture approach, but displayed nonspecific binding of human plasma matrix components that limited the useful assay range. Capillary sandwich assays of CRP in human serum and cerebrospinal fluid were performed using both capture and detection antibodies. The detection antibody was labeled and purified offline to minimize signal from labeled matrix components. Four parameter logistic functions were used to model the data and precision and accuracy were evaluated. During the study, 250 nL injection volumes 2.0 µL/min flow rates were employed, minimizing sample and reagent consumption. The microfluidic system was capable of separating antigens from biological matrices and is potentially portable for patient point-of-care settings. Additionally, the flexible design of the separation capillary allows for the analysis of different clinical markers by changing the antibodies and the low assay volume requirements could lead to less invasive patient sampling techniques.LabVIEW version 7 or later is required to open the attached files.
4

Estudo sobre a determinação de paládio em amostras biológicas pelo método de análise por ativação com nêutrons / Study on the determination of palladium in biological samples for the method of analysis for activation with nêutrons

Cassio Queiroz Cavalcante 12 April 2007 (has links)
O paládio é um dos elementos do grupo da platina presente em baixos teores na natureza. Nos últimos anos com o crescente uso deste elemento nos catalisadores automotivos e nas investigações para o desenvolvimento de drogas anti-tumorais, as suas determinações tornaram-se de grande interesse. No presente trabalho foi feito um estudo sobre a determinação de paládio em amostras biológicas e materiais de referência pelo método de análise por ativação puramente instrumental com nêutrons térmicos (INAA) e epitérmicos (ENAA) separadamente, bem como pela ENAA após separação do paládio por meio das técnicas de extração com solventes e de extração em uma coluna de fase sólida. As amostras analisadas no presente estudo foram: material de referência BCR 723 – Palladium, Platinum and Rhodium in road dust, material catalisador automotivo do teste de proficiência do CCQM-P63 e amostras de tecido bovino contendo Pd preparadas no laboratório. As irradiações das amostras e padrão para INAA e ENAA foram realizadas no reator IEA-R1 sob fluxo de nêutrons térmicos da ordem de 4 x 10 12 n cm-2 s-1 e por um período de 4 h nas irradiações térmicas e de 16 h nas epitérmicas. Depois de adequados tempos de decaimento as medições das atividades gama induzidas das amostras e padrões foram feitas usando um espectrômetro de raios gama constituído de um detector de Ge hiperpuro e eletrônica associada. A concentração de paládio foi calculada pelo método comparativo. O paládio foi medido pelo pico de 88,0 keV do 109Pd localizado numa região do espectro de baixa energia onde ocorre a interferência de picos de raios X, da radiação de freiamento e do efeito Compton do 24Na. A pré-separação do paládio dos elementos interferentes pelo método de extração com solventes foi feita por meio da extração do complexo formado entre o paládio e a dimetilglioxima em clorofórmio. O método de separação por meio da extração em fase sólida consistiu na retenção do paládio em uma coluna de fase sólida de octadecilsilano, contendo complexante N,N-dietil-N’-benzoil tiouréia (DEBT) adsorvido e em seguida fazendo a eluição de paládio com etanol. Alíquotas das soluções resultantes da préseparação, livres de elementos interferentes, foram pipetadas em cápsulas de polietileno e submetidas à ENAA. A comparação entre os resultados de paládio obtidos por diferentes procedimentos de ativação com nêutrons indicou uma boa concordância e uma boa precisão com desvios padrão relativos variando de 2 a 14%. Os rendimentos de recuperação na pré-separação de paládio variaram de 70,9 a 97,7 % e estes resultados dependem do tipo de matriz e da técnica de pré-separação aplicada. Os valores de limite de detecção obtidos para análise do tecido muscular bovino foram de 11,0 e 0,4 &#956;g g-1 pelos métodos de INAA e ENAA, respectivamente. Para o caso do material de referência BCR-723 foram obtidos limites de 24,0 e 1,7 &#956;g g-1, respectivamente na INAA e ENAA e estes resultados indicaram que o limite de detecção depende do tipo de matriz analisada. A irradiação com nêutrons epitérmicos permitiu aumento da sensibilidade devido à redução do problema de interferência e além disso a aplicação da separação prévia do paládio seguida de ENAA proporcionou um aumento da sensibilidade quando comparada com ENAA purament e instrumental. / Palladium is one of platinum group elements present in the nature at very low concentrations. However with the use of this element in the automobile catalyzers Pd became a new pollutant. Besides, Pd has been studied in the preparation of new antitumour drugs. Consequently, there is a need to determine Pd concentrations in biological and environmental samples. This study presents palladium results obtained in the analysis of biological samples and reference materials using instrumental thermal and epithermal neutron activation analysis (INAA and ENAA). The solvent extraction and solid phase extraction separation methods were also applied before ENAA. The samples analyzed in this study were, reference material BCR 723–Palladium, Platinium and Rhodium in road dust, CCQM-P63 automotive catalyst material of the Proficiency Test and bovine tissue samples containing palladium prepared in the laboratory. Samples and palladium synthetic standard were irradiated at the IEA-R1 nuclear research reactor under thermal neutron flux of about 4 x 10 12 n cm-2 s-1, during a period of 4 and 16 h for INAA and ENAA, respectively. The induced gamma activity of 109Pd to the sample and standard was measured using a hyperpure Ge detector coupled to a gamma ray spectrometer. The palladium concentration was calculated by comparative method. The gamma ray energy of 109Pd radioisotope measured was of 88.0 keV, located in a spectrum region of low energy where occurs the interference of X rays, “bremsstrahlung” radiations, as well as Compton effect of 24Na. The pre-separation of palladium from interfering elements by solvent extraction was performed using dimethylglyoxime complexant and chloroform as diluent. In the case of the pre separation procedure using solid reversed phase column, the palladium was retained using N,N-diethyl-N’-benzoyl thiourea complexant and eluted using ethanol. Aliquots of the resulting solutions from the pre-separations, free of interfering elements, were transfered to polyethylene capsules and analyzed by ENAA. Comparisons of palladium results obtained using different procedures of neutron activations analysis showed good agreement and precision. The relative standard deviations of palladium results varied between 2 and 14 %. The recovery yields obtained in the pre-separation procedure varied from 70.9 to 97.7 %, depending on the matrices analyzed and method of separation. Detection limits of 11.0 and 0.4 &#956;g g-1 were obtained in the Pd determination in bovine muscle samples by INAA and ENAA, respectively. For reference material BCR- 723 road dust detection limits of 24.0 and 1.7 &#956;g g-1 were obtained by INAA and ENAA, respectively. These results indicated that the detection limit depends on the matrix type to be analyzed and the epithermal neutron activation allowed high sensitivity for Pd determination due to the reduction of interferences. In regards to palladium determination using pre-separation procedures, the detection limit values indicated that the extraction procedure provides higher sensitivity, when compared to purely instrumental ENAA.
5

Estudo comparativo de m?todos de extra??o para determina??o de fluazuron em plasma bovino por cromatografia l?quida de alta efici?ncia com detec??o em ultravioleta. / Comparison of extraction methods for determining fluazuron in bovine plasma by high-performance liquid chromatography with UV detection.

Ferreira, Thais Paes 11 May 2016 (has links)
Submitted by Leticia Schettini (leticia@ufrrj.br) on 2016-10-04T13:00:01Z No. of bitstreams: 1 2016 - Thais Paes Ferreira.pdf: 1131707 bytes, checksum: c98267296d6293f703188fe1291622db (MD5) / Made available in DSpace on 2016-10-04T13:00:01Z (GMT). No. of bitstreams: 1 2016 - Thais Paes Ferreira.pdf: 1131707 bytes, checksum: c98267296d6293f703188fe1291622db (MD5) Previous issue date: 2016-05-11 / Fluazuron is a benzoylphenylurea acarine growth inhibitor that is marketed for the control of cattle tick. Although the growth regulators are widely studied class, the number of papers describing analytical methods for determining the fluazuron in plasma samples is reduced. The development of a simple and fast analytical method for quantifying fluazuron in bovine plasma by HPLC-UV enables the evaluation of drug plasma profile and can be applied on bioavailability analysis of formulations containing fluazuron. In recent years there has been a technological breakthrough for chromatographic instrumentation, providing rapid, robust and sensitive methods, but the pretreatment of the sample stage becomes the limiting factor in this process. New extraction methods have been developed, however are often complex, expensive methods and are not as sophisticated to handle complex matrices, such as plasma. The aim of this study was a comparative study of three extraction methods: LLE, SPE and matrix solid phase dispersion (MSPD). Pooled plasma samples were used as biological material, partly as raw samples and partly spiked with concentrations of fluazuron. For each extraction method (with exception of DMFS) was conducted using various solvents (ethyl acetate, dichloromethane, diethyl ether, hexane and acetonitrile) in order to evaluate the best extractor solvent. After the extractions the samples were concentrated and analyzed by HPLC/UV. The chromatographic separation was achieved on Kromasil C18 column preceded by guard column of matching chemistry, with mobile phase of acetonitrile: water (80:20, v/v) at flow rate of 1.0 mL/min. The comparative analysis of the extraction procedures was based on selectivity, precision and accuracy of the method. Results showed that LLE not presented accuracy (< 80 and >120%) and precision (CV > 15%) with any solvent tested. SPE method showed good accuracy (80-120%) and precision (CV < 15%) for ethyl acetate, dichloromethane and diethyl ether. MSPD method using ethyl acetate solvent showed good accuracy and precision. However, SPE also allows a lower solvent consumption and shorter analysis time. The validation of the analytical method showed linearity, selectivity, precision, accuracy and, absence matrix effects and residual, thus proving it as suitable for routine analysis; This method showed to be an important investigative tool in the analysis of fluazuron plasma concentration in cattle. Fluazuron topical administration in bovine reached the systemic circulation (Cmax=62,8 ng/mL), was absorbed (tmax=48 hs), while maintaining quantifiable blood plasma levels for up to 14 days after the treatment with a 2,5 mg/Kg dosage. / Fluazuron ? um inibidor do crescimento da classebenzoilfenilur?ia, sendo comercializado para o controle de carrapatos do gado. Embora a classe de reguladores de crescimento sejam amplamente estudada, o n?mero de artigos que descrevem os m?todos anal?ticos para a determina??o do fluazurom em amostras de plasma ? escasso. O desenvolvimento de um m?todo anal?tico simples e r?pido para quantificar fluazuron em plasma bovino por CLAEUV permite a avalia??o do perfil plasm?tico do f?rmaco e pode ser aplicado na an?lise de biodisponibilidade de formula??es contendo fluazurom. Nos ?ltimos anos, tem acontecido um avan?o tecnol?gico para a instrumenta??o cromatogr?fica, proporcionando m?todos r?pidos, eficazes e sens?veis, mas a etapa de pr?-tratamento da amostra torna-se o fator limitante neste processo. Novos m?todos de extra??o t?m sido desenvolvidos, no entanto, muitas das vezes s?om?todos complexos, caros e n?o t?o sofisticados para matrizes complexas como o plasma. O objetivo deste estudo foi um estudo comparativo de tr?s m?todos de extra??o: extra??o l?quido-l?quido (ELL), extra??o em fase s?lida (EFS) e dispers?o de matriz em fase s?lida (DMFS). Ums mistura de amostras de plasma foi utilizada como material biol?gico, uma parte como amostra bruta e outra parcialmente enriquecida com concentra??es de fluazuron. Para cada m?todo de extra??o (exceto DMFS) foram analisadosdiversos solventes (acetato de etila, diclorometano, ?ter diet?lico, hexano e acetonitrila), a fim de avaliar o melhor solvente extrator. Ap?s as extra??es, as amostras foram concentradas e analisadas por CLAE/UV. A separa??o cromatogr?f ica foi obtida na coluna Kromasil C18 precedida de pr?-coluna de fase qu?mica correspondente, com fase m?vel de acetonitrila: ?gua (80:20, v/v) a um fluxo de 1,0 mL /min. A an?lise comparativa dos procedimentos de extra??o foi baseada na seletividade, precis?o e exatid?o do m?todo. Os resultados mostraram que a precis?o ELL n?o apresentou exatid?o (<80 e> 120%) e precis?o (CV> 15%) com nenhum dos solventes analisados. O m?todo EFS mostrou boa exatid?o (80-120%) e precis?o (CV <15%) para o acetato de etila, diclorometano e ?ter diet?lico. O m?todo de DMFS utilizando o solvente acetato de etila mostrou boa exatid?o e precis?o. No entanto, a EFS tamb?m permite um menor consumo de solventes e um tempo curto de an?lise; A valida??o do m?todo anal?tico mostrou linearidade, seletividade, precis?o, exatid?o e, aus?ncia de efeitos de matriz e residual, demonstrando-se adequado para an?lises de rotina; Este m?todo mostrou-se uma ferramenta de investiga??o importante na an?lise de concentra?? plasm?tica em bovinos. Fluazuron administrado por via t?pica em bovinos atingiu a circula??o sist?mica (Cmax = 62,8 ng /ml) e foi absorvido (Tm?x = 48 Hs), se mantendo quantificav?l em n?veis plasm?ticos por at? 14 dias ap?s o tratamento com uma dosagem de 2,5 mg / kg.
6

Estudo sobre a determinação de paládio em amostras biológicas pelo método de análise por ativação com nêutrons / Study on the determination of palladium in biological samples for the method of analysis for activation with nêutrons

Cavalcante, Cassio Queiroz 12 April 2007 (has links)
O paládio é um dos elementos do grupo da platina presente em baixos teores na natureza. Nos últimos anos com o crescente uso deste elemento nos catalisadores automotivos e nas investigações para o desenvolvimento de drogas anti-tumorais, as suas determinações tornaram-se de grande interesse. No presente trabalho foi feito um estudo sobre a determinação de paládio em amostras biológicas e materiais de referência pelo método de análise por ativação puramente instrumental com nêutrons térmicos (INAA) e epitérmicos (ENAA) separadamente, bem como pela ENAA após separação do paládio por meio das técnicas de extração com solventes e de extração em uma coluna de fase sólida. As amostras analisadas no presente estudo foram: material de referência BCR 723 – Palladium, Platinum and Rhodium in road dust, material catalisador automotivo do teste de proficiência do CCQM-P63 e amostras de tecido bovino contendo Pd preparadas no laboratório. As irradiações das amostras e padrão para INAA e ENAA foram realizadas no reator IEA-R1 sob fluxo de nêutrons térmicos da ordem de 4 x 10 12 n cm-2 s-1 e por um período de 4 h nas irradiações térmicas e de 16 h nas epitérmicas. Depois de adequados tempos de decaimento as medições das atividades gama induzidas das amostras e padrões foram feitas usando um espectrômetro de raios gama constituído de um detector de Ge hiperpuro e eletrônica associada. A concentração de paládio foi calculada pelo método comparativo. O paládio foi medido pelo pico de 88,0 keV do 109Pd localizado numa região do espectro de baixa energia onde ocorre a interferência de picos de raios X, da radiação de freiamento e do efeito Compton do 24Na. A pré-separação do paládio dos elementos interferentes pelo método de extração com solventes foi feita por meio da extração do complexo formado entre o paládio e a dimetilglioxima em clorofórmio. O método de separação por meio da extração em fase sólida consistiu na retenção do paládio em uma coluna de fase sólida de octadecilsilano, contendo complexante N,N-dietil-N’-benzoil tiouréia (DEBT) adsorvido e em seguida fazendo a eluição de paládio com etanol. Alíquotas das soluções resultantes da préseparação, livres de elementos interferentes, foram pipetadas em cápsulas de polietileno e submetidas à ENAA. A comparação entre os resultados de paládio obtidos por diferentes procedimentos de ativação com nêutrons indicou uma boa concordância e uma boa precisão com desvios padrão relativos variando de 2 a 14%. Os rendimentos de recuperação na pré-separação de paládio variaram de 70,9 a 97,7 % e estes resultados dependem do tipo de matriz e da técnica de pré-separação aplicada. Os valores de limite de detecção obtidos para análise do tecido muscular bovino foram de 11,0 e 0,4 &#956;g g-1 pelos métodos de INAA e ENAA, respectivamente. Para o caso do material de referência BCR-723 foram obtidos limites de 24,0 e 1,7 &#956;g g-1, respectivamente na INAA e ENAA e estes resultados indicaram que o limite de detecção depende do tipo de matriz analisada. A irradiação com nêutrons epitérmicos permitiu aumento da sensibilidade devido à redução do problema de interferência e além disso a aplicação da separação prévia do paládio seguida de ENAA proporcionou um aumento da sensibilidade quando comparada com ENAA purament e instrumental. / Palladium is one of platinum group elements present in the nature at very low concentrations. However with the use of this element in the automobile catalyzers Pd became a new pollutant. Besides, Pd has been studied in the preparation of new antitumour drugs. Consequently, there is a need to determine Pd concentrations in biological and environmental samples. This study presents palladium results obtained in the analysis of biological samples and reference materials using instrumental thermal and epithermal neutron activation analysis (INAA and ENAA). The solvent extraction and solid phase extraction separation methods were also applied before ENAA. The samples analyzed in this study were, reference material BCR 723–Palladium, Platinium and Rhodium in road dust, CCQM-P63 automotive catalyst material of the Proficiency Test and bovine tissue samples containing palladium prepared in the laboratory. Samples and palladium synthetic standard were irradiated at the IEA-R1 nuclear research reactor under thermal neutron flux of about 4 x 10 12 n cm-2 s-1, during a period of 4 and 16 h for INAA and ENAA, respectively. The induced gamma activity of 109Pd to the sample and standard was measured using a hyperpure Ge detector coupled to a gamma ray spectrometer. The palladium concentration was calculated by comparative method. The gamma ray energy of 109Pd radioisotope measured was of 88.0 keV, located in a spectrum region of low energy where occurs the interference of X rays, “bremsstrahlung" radiations, as well as Compton effect of 24Na. The pre-separation of palladium from interfering elements by solvent extraction was performed using dimethylglyoxime complexant and chloroform as diluent. In the case of the pre separation procedure using solid reversed phase column, the palladium was retained using N,N-diethyl-N’-benzoyl thiourea complexant and eluted using ethanol. Aliquots of the resulting solutions from the pre-separations, free of interfering elements, were transfered to polyethylene capsules and analyzed by ENAA. Comparisons of palladium results obtained using different procedures of neutron activations analysis showed good agreement and precision. The relative standard deviations of palladium results varied between 2 and 14 %. The recovery yields obtained in the pre-separation procedure varied from 70.9 to 97.7 %, depending on the matrices analyzed and method of separation. Detection limits of 11.0 and 0.4 &#956;g g-1 were obtained in the Pd determination in bovine muscle samples by INAA and ENAA, respectively. For reference material BCR- 723 road dust detection limits of 24.0 and 1.7 &#956;g g-1 were obtained by INAA and ENAA, respectively. These results indicated that the detection limit depends on the matrix type to be analyzed and the epithermal neutron activation allowed high sensitivity for Pd determination due to the reduction of interferences. In regards to palladium determination using pre-separation procedures, the detection limit values indicated that the extraction procedure provides higher sensitivity, when compared to purely instrumental ENAA.
7

Methods for Confirmatory Analysis of Methamphetamine in Biological Samples

Brown, Stacy D. 01 January 2012 (has links)
Methamphetamine is the most common amphetamine used and, along with 3,4-methylenedioxymethamphetamine (MDMA, Ecstasy), is considered part of a worldwide drug epidemic. Monitoring metham-phetamine levels in the body is important for purposes of drug screening for employment, criminal investigations, and therapeutic drug monitoring. While methamphetamine is suitable for detection using immunoassay techniques, these methods tend to have significant cross reactivity with other compounds. Over the last decade, more than eighty different quantitative, confirmatory analytical methods for measuring methamphetamine in biological samples have been published in the scientific literature. Analytical instrumentation used in these methods includes gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry (LC-MS), capillary electrophoresis (CE), among others. These assays are capable of quantifying methamphetamine concentrations in a variety of biological matrices, including blood, plasma, urine, hair, and fingernails. Some of these techniques can achieve detection as low as 0.1 ng/mL (1 ppb) concentra-tions. The strengths and limitations of these methodologies will be discussed in the context of methamphetamine analysis. Additionally, methods that can simultaneously measure methamphetamine levels as well as metabolites and other drugs of abuse will be highlighted.
8

Syntheses and Sensing Applications of Modified Noble Metal-containing Nanoparticles

Yu, Zhao 30 September 2021 (has links)
No description available.
9

Development of Liquid-based Separation Techniques using Tailored Surfaces for Analysis of Biological Samples

Hardenborg, Emilia January 2008 (has links)
Development and improvement of analytical techniques are vital in analytical chemistry research. This thesis describes the development and use of tailored surfaces for bioanalytical applications. In sample preparation, solid phase extraction is often used and the development of a protocol for extraction on a molecular imprinted polymer (MISPE) directly from plasma sample is presented. Molecular imprinted polymers (MIP) offer selective sorbents for the imprinted analyte. MISPE has mainly been used in organic phase but in this thesis the development of a protocol for direct extraction of the analyte form an aqueous phase is described. For analysis of complex samples a separation step is often needed. The growing interest in analysis of biological samples and analysis of the human proteome and potential biomarkers has increased the interest in developing new separation techniques. Capillary electrophoresis (CE) has evolved into an important technique for use in analysis of body fluids. In this thesis a novel polyamine coating named PolyE 323 tailored for minimizing the adsorption of basic proteins to the surface is introduced. A straightforward coating protocol, with four simple rinsing steps, was developed. The coating was highly reproducible and useable over a wide pH range. Successful protein separations on PolyE-323-coated capillaries coupled to electrospray ionization mass spectrometry (ESI-MS) were demonstrated. The coated capillaries were also used in studies of protein content of aqueous humor samples from cataract patients as a complement to capillary liquid chromatography. In the studies presented the protein content of aqueous humor samples from two clinical groups was compared. By using capillary liquid separation techniques coupled to matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) and MS/MS in combination with isobaric tags for relative and absolute quantitation (iTRAQ) the identity and relative concentrations of proteins in the samples were evaluated. Earlier studies of the proteins in these kinds of samples have mainly been done with techniques using immunological detection where the proteins of interest were chosen in advance. In this thesis it was shown that liquid-based separation techniques are a good complement and by using the mass spectrometry approach presented the protein content of the samples could be evaluated without bias.
10

Determinação de elementos essenciais e contaminantes em amostras biológicas empregando espectrometria atômica

Santos, Luiz Raimundo Seneterri Silva Rodrigues dos January 2010 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-06T15:11:17Z No. of bitstreams: 1 DISSERTAÇÃO LUIZ RAIMUNDO S.S.R.SANTOS.pdf: 1266644 bytes, checksum: 450e692c86f2ffc5bc25ffa7e76b9e3d (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-06T15:37:29Z (GMT) No. of bitstreams: 1 DISSERTAÇÃO LUIZ RAIMUNDO S.S.R.SANTOS.pdf: 1266644 bytes, checksum: 450e692c86f2ffc5bc25ffa7e76b9e3d (MD5) / Made available in DSpace on 2016-09-06T15:37:29Z (GMT). No. of bitstreams: 1 DISSERTAÇÃO LUIZ RAIMUNDO S.S.R.SANTOS.pdf: 1266644 bytes, checksum: 450e692c86f2ffc5bc25ffa7e76b9e3d (MD5) / O estudo de elementos essenciais e contaminantes nas amostras biológicas é de grande importância visto que a variação da concentração destes é um parâmetro para detecção de diversas doenças e distúrbios metabólicos provocados pela exposição a substâncias tóxicas e medicamentos. O objetivo deste trabalho foi propor um método analítico visando avaliar o efeito da furosemida (diurético de alça) sobre a composição mineral (Mg, Cu, Fe, Se, Zn, Cd e Pb) em amostras biológicas (fígado, rim, coração, pulmão e soro) de ratos Wistar por espectrometria de emissão óptica com plasma indutivamente acoplado (ICP OES). Para a decomposição das amostras foi utilizado um procedimento por via úmida, com adição de ácido nítrico e peróxido de hidrogênio, empregando forno de microondas com cavidade. As figuras analíticas de mérito (precisão, limites de detecção (LOD) e quantificação (LOQ) e efeito de matriz) foram determinadas para o procedimento proposto. A exatidão foi verificada com material de referência certificado fígado bovino NIST 1577b e por comparação com método de referência da AOAC (Association of Official Analytical Chemists). O procedimento proposto foi aplicado para avaliação dos efeitos da furosemida sobre a composição corporal de elementos essenciais e contaminantes de ratos Wistar. Os dados para Se, Cd e Pb foram abaixo do LOQ, sendo necessário a utilização de técnicas mais sensíveis como GF AAS e ICP-MS para a quantificação desses elementos em amostras biológicas. Em relação ao comportamento dos minerais nas amostras biológicas estudadas, o Cu, nas amostras biológicas dos ratos machos, este apresenta uma redução no fígado, rim e coração, mantendo-se constante no pulmão. Nas fêmeas há um aumento no fígado e redução no rim, coração e pulmão. Para o Fe, o comportamento é semelhante entre machos e fêmeas, com redução no fígado, rim e soro e aumento no coração e pulmão. O Mg apresenta uma constância no fígado e pulmão, redução no rim, coração e aumento no soro para machos, enquanto para fêmeas, em fígado e rim permanecem constantes e há redução no coração, pulmão e soro. Já o Zn reduz no fígado e rim dos machos e se mantém constante no coração e pulmão, sendo o inverso para as fêmeas. Foi encontrando como resultados uma extração dos elementos Mg, Cu e Zn em todos os tecidos biológicos estudados em uma magnitude de 16,8; 15,1 e 6,4 % para ratos machos e 13,0; 16,5 e 8,1 % para fêmeas, após a administração da furosemida em todos os animais estudados. O Fe apresentou um aumento de 21,8% e 5,1%, em todos os tecidos biológicos estudados, para ratos machos e fêmeas respectivamente, concluindo que a furosemida não traz prejuízos para a saúde com relação à perda de elementos essenciais / The study of essential elements and contaminants in biological samples is of great importance since the variation of the concentration of these is a parameter for the detection of various diseases and metabolic disorders caused by exposure to toxic substances and medicines. The aim of this study was to propose an analytical method to evaluate the effect of furosemide (loop diuretic) on the mineral composition (Mg, Cu, Fe, Se, Zn, Cd and Pb) in biological samples (liver, kidney, heart, lung and serum) of rats by optical emission spectrometry with inductively coupled plasma (ICP OES). For decomposition of the samples we used a procedure by wet, with the addition of nitric acid and hydrogen peroxide, using a microwave cavity. The analytical figures of merit (precision, limit of detection (LOD) and quantification (LOQ) and matrix effect) were determined for the proposed procedure. The accuracy was checked with certified reference material NIST 1577b bovine liver and by comparison with reference method AOAC (Association of Official Analytical Chemists). The proposed procedure was applied to assess the effects of furosemide on body composition of essential elements and contaminants in rats. The data for Se, Cd and Pb were below the LOQ, necessitating the use of more sensitive techniques such as GF AAS and ICP-MS for quantification of these elements in biological samples. As for the behavior of minerals in biological samples studied, the Cu in biological samples from male rats, this presents a reduction in the liver, kidney and heart, remaining constant in the lung. In females there is an increase in the liver and reduction in kidney, heart and lung. For Fe, the behavior is similar between males and females, with a reduction in the liver, kidney and serum and increased heart and lung. Magnesium has a constancy in the liver and lung, reduction in kidney, heart and an increase in serum for males as for females, liver and kidney remain constant and there is a reduction in heart, lung and serum. Already reduces the Zn in the liver and kidney of males and remained constant in the heart and lungs, and the converse for females. Was found as a result of the extraction elements Mg, Cu and Zn in all biological tissues studied in a magnitude of 16.8, 15.1 and 6.4% for males and 13.0, 16.5 and 8.1 % for females, after administration of furosemide in all animals studied. Fe showed an increase of 21.8% and 5.1% in all biological tissues studied, for males and females respectively, concluding that furosemide does not bring harm to health in relation to loss of essential elements

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