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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.
81

Quimiometria aplicada à cromatografia líquida multidimensional capilar hifenizada a espectrometria de massas sequencial para proteômica shotgun / Chemometric approach to a capillary multidimensional liquid chromatography coupled to tandem mass spectrometry for shotgun proteomics

Batiston, Weliton Pedro 19 February 2015 (has links)
O sequenciamento genético do DNA humano permitiu maior compreensão da funcionalidade dos seres vivos e principalmente a causa de muitas doenças. Entretanto, os estudos em genética têm se limitado a resolverem os problemas da ciência, e atualmente, a solução para o avanço nessa área tem se atribuído à proteômica. Dessa forma, a pesquisa em química analítica intensificou-se na busca de estratégias melhores para a caracterização de proteomas, em três aspectos principais: preparo de amostra, desenvolvimento da instrumentação analítica e bioinformática. Verifica-se a possibilidade da aplicação de muitas técnicas, atualmente, destaca-se a análise de peptídeos (proteômica shotgun) por cromatografia líquida multidimensional acoplada à espectrometria de massas sequencial (LC/LC-MS/MS), devido à possibilidade de automatização, minimização dos problemas e resultados satisfatórios na análise de amostras biológicas complexas. Portanto, neste trabalho desenvolveu-se um método LC/LC-MS/MS (modalidade on-line column switching) o qual se constitui de coluna trocadora catiônica (homemade), trap de aprisionamento e limpeza, coluna capilar hidrofóbica e separação e detecção por espectrometria de massas sequencial automatizada. Com a proposta de uma instrumentação analítica aperfeiçoada, realizamos a confecção de um trap com partículas de elevada retenção dos peptídeos, o que permite ótima recuperação de amostra. Por se tratar de uma técnica de elevada complexidade instrumental, devido a difícil compatibilidade entre as dimensões cromatográficas, possíveis perda de analito no processo e elevado tempo de análise, propomos uma nova abordagem de otimização, por meio de estudos quimiométricos. Assim, neste trabalho, foram avaliados doze parâmetros instrumentais e destes houve uma simplificação de apenas dois fatores, responsáveis por 95% da resposta ótima do método. Este fato permitiu valores da cobertura da proteína de BSA (82,54%), número de peptídeos (65) e score (2134,05) superiores aos reportados na literatura, os quais apresentam tempos de análise maiores. Este estudo fornece informações do comportamento químico dos peptídeos em relação ao método proposto, por meio de uma superfície de resposta e equação matemática que pode contribuir para a aplicação em diferentes proteomas. / The genetic sequence of human DNA has helped the comprehension of life and principally the cause of various diseases. However, genetic studies have limited to resolve science problems and currently solutions to advance in this field have been attributed to proteomics. Thus, the analytical chemistry has intensified on the search for a better strategy to proteomic characterization in three principal aspects: sample preparation, development of analytical instrumentation, and bioinformatics. Proteomics involves the application of many techniques, currently; the peptide analyses (shotgun proteomics) by multidimensional liquid chromatography coupled to tandem mass spectrometry (LC/LC-MS/MS) is the state of the art. The main reasons are because it allows full system automation, less problems in repeatability, and adequate results in analysis of highly complex biological samples. Therefore, this dissertation developed the method LC/LC-MS/MS (modality on-line column switching), this has a cation exchange column (homemade), trap column to clean, hydrophobic capillary column and separation and detection by tandem mass spectrometry. We have proposed an improved analytical instrumentation, with a homemade trap that particles have high retention of peptide, which permit great recuperation of samples. Because it is an instrumental technique difficult, such as, obtain compatibility between the chromatography dimensions, can lose samples in the process and long time analysis, we have proposed a new optimization approach with chemometric analysis of data. On that, were evaluated twelve instrumental parameters and there was a simplification only two factors, these were responsible for 95% of greater response of method. As a result, the coverage of BSA protein was 82,54%, number of peptides 65 and score of 2134,05 values of high significance if compare from that there are in literature that presented greater time analysis. This work describes information about chemistry of peptides to method proposed through a surface of response and math equation that can contribute to different proteomes.
82

Analyse multi-résidus de sulfonamides et de leurs métabolites dans les tissus d’origine animale / Multiresidue analysis of sulfonamides and their metabolites in animal tissues

Hiba, Abdallah 17 December 2014 (has links)
Les sulfonamides sont parmi les antibiotiques les plus couramment utilisés en élevage. Ils peuvent en effet, si leur utilisation n’est pas conduite de manière raisonnable, être une source de nombreux risques pour la santé publique. Au Liban, il n’existe pas à l’heure actuelle de règlementation fixant les limites de résidus des sulfonamides dans les tissus d'origine animale. En outre, aucune investigation sur la présence des résidus des sulfonamides sous leurs formes actives ou métabolisée dans les denrées animales n’a été menée. L'analyse d'une matrice complexe telle que la viande a nécessité la mise en œuvre d’une préparation d'échantillon rigoureuse afin obtenir une analyse reproductible, et suffisamment sensible pour atteindre les limites de détection requises. Cette thèse décrit le développement de deux méthodes analytiques pour la détermination de sulfonamides et de leurs métabolites à l’état de traces dans les tissus d’origine animale (bœuf, volaille, porc…). Elles sont basées sur une étape d'extraction utilisant la méthode QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) suivie d'une analyse par HPLC couplée à un analyseur triple quadripôle MS/MS ou LTQ-Orbitrap Velos. Les performances analytiques de ces méthodes ont été évaluées et comparées. Les méthodes d’analyse ont été validées suivant les recommandations de la décision de l’UE (2002/657/EC) et lors d’une étude de validation inter-laboratoires organisée par FAPAS (Food Analysis Performance Assessment Scheme). Au vu des performances obtenues, une étude de contrôle a été réalisée sur les résidus des sulfonamides et de leurs métabolites dans plus de 300 échantillons de différents tissus d’origine animale dérivant de poulets de chair, bœufs, brebis et porcs collectés dans différentes régions d’élevage libanaises / Sulfonamides are amongst the most commonly used veterinary antibiotics. The uncontrolled exposure to sulfonamides upon consumption of meat products can be harmful to human health. In Lebanon, there are no current regulations that specify the safe levels of sulfonamides in animal products. In addition, no studies describing the presence of sulfonamides residues in their active or metabolized form in animal tissues exist. The analysis of residues at trace levels in complex matrices such as meat required the implementation of a rigorous sample preparation and analytical protocol that yields reproducible results at very low concentration levels. This thesis describes the development of two analytical methods for the determination of sulfonamides and their metabolites in animal tissues (e.g. poultry, sheep, pork) at trace levels. They are both based on an extraction step using QuEChERS extraction (Quick, Easy, Cheap, Effective, Rugged and Safe) followed by HPLC. In terms of mass analysers the use of LTQ-Orbitrap Velos and triple quadrupole MS/MS was optimized and the figures of merit were compared. The analytical methods were validated according to the EU decision (2002/657 / EC) criteria and by the participation in an inter-laboratory validation study organized by FAPAS (Food Analysis Performance Assessment Scheme). The methods were applied to carry out a monitoring study to detect and quantify residues of sulfonamides and their metabolites in more than 300 different samples of animal tissues derived from poultry, beef, sheep and pork collected from different regions of Lebanon..
83

Avaliação da presença de fármacos, por LC-MS/MS, em águas superficiais pré e pós-tratamento convencional por ensaio Jar-test e caracterização do risco humano / Evaluation of the presence of drugs by LC-MS/MS in surface water before and after conventional treatment by jar-test test and the characterization of human risk

Pais, Mariana Castello Novo 03 June 2013 (has links)
O aumento crescente da população brasileira em combinação com o uso abusivo de medicamentos no mercado nacional, aliados à falta de saneamento básico e de políticas públicas para o correto gerenciamento de alguns tipos de resíduos têm resultado na presença de compostos farmacêuticos em ambientes aquáticos. Estudos indicam que várias dessas substâncias parecem ser persistentes no ambiente e algumas vezes, resistem até mesmo às estações de tratamento de água, fazendo-se presentes na água tratada, que chega à população. O presente trabalho visou analisar quantitativamente a presença dos anti-inflamatórios e do analgésico mais comumente consumido no Brasil: diclofenaco, cetoprofeno, naproxeno, indometacina, ibuprofeno e o paracetamol em águas superficiais, por LC-MS/MS com extração em fase sólida, antes e depois do tratamento convencional, em escala laboratorial pelo ensaio de Jar-Test, bem como caracterizar o risco humano pela presença destes compostos na água após o tratamento. Os métodos utilizados na quantificação destes fármacos apresentaram bons resultados: a análise cromatográfica obteve coeficientes de correlação entre 0,9952-0,9991, com limites de quantificação de 0,5ng/mL- 50ng/mL e desvios padrões entre (0,08-2,08); na recuperação do método de extração em fase sólida o diclofenaco, o cetoprofeno, o naproxeno e a indometacina apresentaram cerca de 100% de recuperação, o ibuprofeno apresentou apenas 48%(±9,37) de recuperação e o paracetamol aproximadamente 19,84% (±2,52); no ensaio de jar-test, observou-se que apenas o cetoprofeno e o ibuprofeno não foram removidos completamente no tratamento utilizado (remoção de 0-15% do cetoprofeno e de 0-35% do ibuprofeno). Amostras ambientais foram coletadas e tratadas pelo ensaio de Jar-Test, e os valores obtidos para o cetoprofeno e ibuprofeno após o tratamento foram de 18,67-19,65ng/L e 147ng/L, respectivamente. Através de cálculos, com a dose de referência de cada um dos compostos e considerando as características desta exposição, foi possível concluir que nestas concentrações o cetoprofeno e o ibuprofeno não causam risco à saúde humana. / The increasing population growth in combination with the misuse of drugs in the domestic market, coupled with the lack of sanitation and public policies for proper management of some types of waste have resulted in the presence of pharmaceutical compounds in aquatic environments. Studies indicate that several of these substances appear to be persistent in the environment and sometimes even resistant to water treatment plants, being present in the treated water which reaches the population. This study aimed to analyze quantitatively the presence of anti-inflammatory and analgesic most commonly consumed in Brazil: diclofenac, ketoprofen, naproxen, indomethacin, ibuprofen and paracetamol in surface waters by LC-MS/MS with solid phase extraction prior and after conventional treatment in a laboratory scale by using Jar-test assay, and to determine the human risk posed by the presence of these compounds in the water after treatment. The methods used to quantify these drugs showed good results: a chromatographic analysis obtained correlation coefficients between 0.9952 to 0.9991, with limits of quantification of 0.5 ng/mL- 50ng/mL and standard deviations between (0.08 - 2.08); recovery method of solid phase extraction to diclofenac, ketoprofen, naproxen and indomethacin showed about 100% recovery, ibuprofen showed only 48% (± 9.37) and paracetamol approximately 19 84% (± 2.52) recovery; in the jar-test, it was observed that only ketoprofen and ibuprofen were not completely removed (removal: 0-15% of ketoprofen and 0-35% of ibuprofen). Environmental samples were collected and handled by jar-test test, and the values obtained for ketoprofen and ibuprofen after treatment were 18.67 to 19.65 ng / L and 147ng / L, respectively. By calculation with a reference dose of each compound and considering the characteristics of this display, it was concluded that these concentrations of ketoprofen and ibuprofen do not cause risk to human health.
84

Devenir des antibiotiques lors du traitement aérobie et anaérobie des boues de STEPs pour une valorisation agronomique / The fate of antibiotics during aerobic and anaerobic treatment of sludges from WWTPs for an agronomic valorisation

Ezzariai, Amine 15 September 2018 (has links)
L’utilisation massive des antibiotiques contribue à leur accumulation dans les boues des stations d’épurations. L’application directe des boues est parmi les sources de dissémination des antibiotiques et des gènes de résistance aux antibiotiques. Le compostage et la méthanisation sont parmi les bioprocédés de traitement des boues qui permettent d’éliminer ou réduire les teneurs de certains antibiotiques. Dans ce travail, une boue primaire de la STEP de Marrakech a été contaminée par trois familles d’antibiotiques (macrolides, tétracyclines, fluoroquinolones) pour conduire 4 essais de compostage à différentes doses (dont un essai témoin) et un essai deméthanisation en mode semi-continu. Les résultats du compostage ont montré que l’augmentation des concentrations d’antibiotiques retarde la dégradation de la matière organique et affecte le ratioC/N. De même, la phase thermophile est perturbée, retardée et réduite dans le temps. Pour la méthanisation, une concentration unique et réaliste a été testée. Dans ces conditions, aucun effet sur la production du biogaz ou sur la dégradation de la matière organique n’a été observé. Afin de suivre la dissipation des trois familles d’antibiotiques utilisées au cours du compostage et de la méthanisation, une approche analytique basée sur l’extraction accélérée par solvant (ASE) suivie par l’application d’une méthode des ajouts dosés avant quantification par chromatographie liquide couplée à de la spectrométrie de masse en tandem (UPLC-MS/MS) a du être mise en point. Le compostage et la méthanisation permettent de réduire significativement les concentrations des molécules parents appartenant à la famille des macrolides et des tétracyclines. Par contre,l’élimination des fluoroquinolones est non-significative et ne dépasse pas 30%. Au cours du compostage, la dissipation des macrolides se fait en phase de stabilisation tandis que la phase de maturation est impliquée dans la dissipation des tétracyclines. Les concentrations encirprofloxacine (fluoroquinolone) semblent légèrement évoluer au cours du procédé probablement en raison d’une adsorption/désorption sur le co-substrat lignocellulosique utilisé. Concernant la méthanisation, l’élimination des macrolides et des tétracyclines est significative durant la stabilisation du procédé mais n’atteinds pas les rendements observés lors du compostage. Ladiminution des concentrations des molécules parents est probablement accompagnée par une biotransformation des antibiotiques sous forme de métabolites qui à ce stade ne sont pas connus.La question de la rémanence de certaines molécules comme les fluoroquinolones, interpelle quand au risque d’antibiorésistance. Ainsi, la valorisation des composts/digestats comme amendements organiques des sols dois à terme conduire à une réflexion concernant la réglementation qui inclus la présence de molécule de la classe des antibiotiques. / The intensive use of antibiotics for human purposes leads to their presence and accumulation inthe sludge produced from wastewater treatment plants. The direct application of sludge is amongthe sources of dissemination of antibiotics and antibiotics resistance genes. Composting andanaerobic digestion are some of the most used bioprocess for sludge treatment, and which allowthe removal/decrease of some antibiotics families. In this work, a primary sludge from thewastewater treatment plant of Marrakesh was spiked using 3 families of antibiotics (macrolides,tetracyclines, fluoroquinolones) to conduct (1) 4 composting experiments with variousconcentrations levels, and (2) an anaerobic digestion experiment in a semi-continuous mode.Composting results showed that the organic matter degradation was delayed and the C/N ratiowas affected by an increase of antibiotics concentrations. Likewise, the thermophilic stage wasdisturbed, the heat release was affected and the coming of the temperature maxima was delayed.In the other hand, one realistic concentration was used during the anaerobic digestion. In thiscondition, no effect was observed especially on the biogas production as well as the organicmatter degradation. To assess the fate of antibiotics during composting and anaerobic digestion,an analytical approach based on the accelerated solvent extraction followed by the standardaddition method and the UPLC-MS/MS was developed. Composting and anaerobic digestion leadto a significant removal of parent compounds belonging to the family of macrolides andtetracyclines. In contrast, the fluoroquinolones removal is not-significant and has not exceeded30%. During composting, the thermophilic stage was responsible on macrolides elimination. Incontrast, the maturation stage was more implicated on the removal of tetracyclines. Ciprofloxacin(fluoroquinolone) showed some fluctuations in concentrations. The sorption/desorption on palmrachis could probably explain the observed behavior of this molecule during composting. Duringthe anaerobic digestion, the removal of macrolides and tetracyclines was significant, within thestabilization, but still lower than the observed ones during composting. The decrease of parentcompounds of antibiotics is probably accompanied by a biotransformation of these compounds inunknown metabolites. The presence of recalcitrant compounds after the bioprocess could promotethe development of resistant bacteria including pathogens. In the future regulations, thevalorization of compost/digestate as an amendment of agricultural soil requires taking into accountthe presence of antibiotics.
85

Detec??o de metamidof?s em solos por m?todos ecotoxicol?gico e cromatografia l?quida acoplada ? espectrometria de massas sequencial (LC-MS/MS)

Chiquetti, Samanta Cristina 27 June 2013 (has links)
Made available in DSpace on 2014-12-17T15:42:27Z (GMT). No. of bitstreams: 1 SamantaCC_TESE.pdf: 1799576 bytes, checksum: cb7da23d45f604db518addfb2da4a069 (MD5) Previous issue date: 2013-06-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Soil contamination by pesticides is an environmental problem that needs to be monitored and avoided. However, the lack of fast, accurate and low cost analytical methods for discovering residual pesticide in complex matrices, such as soil, is a problem still unresolved. This problem needs to be solved before we are able to assess the quality of environmental samples. The intensive use of pesticides has increased since the 60s, because the dependence of their use, causing biological imbalances and promoting resistance and recurrence of high populations of pests and pathogens (upwelling). This has contributed to the appearance of new pests that were previously under natural control. To develop analytical methods that are able to quantify residues pesticide in complex environment. It is still a challenge for many laboratories. The integration of two analytical methods one ecotoxicological and another chemical demonstrates the potential for environmental analysis of methamidophos. The aim of this study was to evaluate an ecotoxicological method as "screening" analytical methamidophos in the soil and perform analytical confirmation in the samples of the concentration of the analyte by chemical method LC-MS/MS In this work we tested two soils: a clayey and sandy, both in contact with the kinetic methamidophos model followed pseudo-second order. The clay soil showed higher absorption of methamidophos and followed the Freundlich model, while the sandy, the Langmuir model. The chemical method was validated LC-MS/MS satisfactory, showing all parameters of linearity, range, precision, accuracy, and sensitivity adequate. In chronic ecotoxicological tests with C. dubia, the NOEC was 4.93 and 3.24 for ng L-1 of methamidophos to elutriate assays of sandy and clay soils, respectively. The method for ecotoxicological levels was more sensitive than LC-MS/MS detection of methamidophos, loamy and sandy soils. However, decreasing the concentration of the standard for analytical methamidophos and adjusting for the validation conditions chemical acquires a limit of quantification (LOQ) in ng L-1, consistent with the provisions of ecotoxicological test. The methods described should be used as an analytical tool for methamidophos in soil, and the ecotoxicological analysis can be used as a "screening" and LC-MS/MS as confirmatory analysis of the analyte molecule, confirming the objectives of this work / A contamina??o de solos por agrot?xicos ? um problema ambiental que precisa ser monitorado e evitado. Por?m, a falta de m?todos de an?lise r?pidos, precisos e de baixo custo, para res?duos de agrot?xicos em matrizes complexas, como o solo, ? um problema ainda sem solu??o e precisa ser resolvido para que se possa avaliar a qualidade de amostras ambientais. O uso intensivo de agrot?xicos tem aumentado desde a d?cada de 60, causando a depend?ncia do seu uso, provocando desequil?brios biol?gicos e favorecendo a resist?ncia e a reincid?ncia de altas popula??es das pragas e pat?genos (ressurg?ncia), o que contribui com o aparecimento de novas pragas que anteriormente estavam sob o controle natural. O desenvolvimento de m?todos anal?ticos que atendam as legisla??es ambientais de quantificar res?duos de pesticidas em matrizes complexas ambientais continua sendo um desafio para v?rios laborat?rios. O objetivo deste trabalho foi avaliar um m?todo ecotoxicol?gico como screening anal?tico do metamidof?s em solos e realizar a confirma??o anal?tica das concentra??es do analito nas amostras pelo m?todo qu?mico LC-MS/MS.A integra??o de dois m?todos anal?ticos, um ecotoxicol?gico e outro qu?mico, demonstra potencial para a an?lise ambiental do metamidof?s. Neste trabalho foram testados dois solos: um argiloso e outro arenoso, ambos seguiram o modelo cin?tico de pseudo-segunda ordem para a adsor??o do metamidof?s. O solo argiloso apresentou maior adsor??o de metamidof?s e seguiu o modelo de Freundlich, enquanto o arenoso, o modelo de Langmuir. O m?todo qu?mico LC-MS/MS validado foi satisfat?rio, apresentando todos os par?metros de linearidade, intervalo, precis?o, exatid?o e sensibilidade adequados. Nos ensaios ecotoxicol?gicos cr?nicos com Ceriodapnhia dubia, as CENO foram 4,93 e 3,24 ng L-1 de metamidof?s para os elutriatos dos solos arenoso e argiloso, respectivamente. O m?todo ecotoxicol?gico apresentou-se mais sens?vel que o LC-MS/MS na detec??o do metamidof?s, nos solos argiloso e arenoso. No entanto, diminuindo-se a concentra??o do padr?o anal?tico do metamidof?s e ajustando-se as condi??es de valida??o qu?mica, adquire-se um limite de quantifica??o (LOQ) em ng L-1, compat?vel com o estabelecido no ensaio ecotoxicol?gico. Os m?todos utilizados apresentam-se como uma boa ferramenta anal?tica para o metamidof?s em solos, sendo que a an?lise ecotoxicol?gica poder? ser utilizada como um screening e o LC-MS/MS como an?lise confirmat?ria da mol?cula do analito, confirmando os objetivos desse trabalho
86

Quimiometria aplicada à cromatografia líquida multidimensional capilar hifenizada a espectrometria de massas sequencial para proteômica shotgun / Chemometric approach to a capillary multidimensional liquid chromatography coupled to tandem mass spectrometry for shotgun proteomics

Weliton Pedro Batiston 19 February 2015 (has links)
O sequenciamento genético do DNA humano permitiu maior compreensão da funcionalidade dos seres vivos e principalmente a causa de muitas doenças. Entretanto, os estudos em genética têm se limitado a resolverem os problemas da ciência, e atualmente, a solução para o avanço nessa área tem se atribuído à proteômica. Dessa forma, a pesquisa em química analítica intensificou-se na busca de estratégias melhores para a caracterização de proteomas, em três aspectos principais: preparo de amostra, desenvolvimento da instrumentação analítica e bioinformática. Verifica-se a possibilidade da aplicação de muitas técnicas, atualmente, destaca-se a análise de peptídeos (proteômica shotgun) por cromatografia líquida multidimensional acoplada à espectrometria de massas sequencial (LC/LC-MS/MS), devido à possibilidade de automatização, minimização dos problemas e resultados satisfatórios na análise de amostras biológicas complexas. Portanto, neste trabalho desenvolveu-se um método LC/LC-MS/MS (modalidade on-line column switching) o qual se constitui de coluna trocadora catiônica (homemade), trap de aprisionamento e limpeza, coluna capilar hidrofóbica e separação e detecção por espectrometria de massas sequencial automatizada. Com a proposta de uma instrumentação analítica aperfeiçoada, realizamos a confecção de um trap com partículas de elevada retenção dos peptídeos, o que permite ótima recuperação de amostra. Por se tratar de uma técnica de elevada complexidade instrumental, devido a difícil compatibilidade entre as dimensões cromatográficas, possíveis perda de analito no processo e elevado tempo de análise, propomos uma nova abordagem de otimização, por meio de estudos quimiométricos. Assim, neste trabalho, foram avaliados doze parâmetros instrumentais e destes houve uma simplificação de apenas dois fatores, responsáveis por 95% da resposta ótima do método. Este fato permitiu valores da cobertura da proteína de BSA (82,54%), número de peptídeos (65) e score (2134,05) superiores aos reportados na literatura, os quais apresentam tempos de análise maiores. Este estudo fornece informações do comportamento químico dos peptídeos em relação ao método proposto, por meio de uma superfície de resposta e equação matemática que pode contribuir para a aplicação em diferentes proteomas. / The genetic sequence of human DNA has helped the comprehension of life and principally the cause of various diseases. However, genetic studies have limited to resolve science problems and currently solutions to advance in this field have been attributed to proteomics. Thus, the analytical chemistry has intensified on the search for a better strategy to proteomic characterization in three principal aspects: sample preparation, development of analytical instrumentation, and bioinformatics. Proteomics involves the application of many techniques, currently; the peptide analyses (shotgun proteomics) by multidimensional liquid chromatography coupled to tandem mass spectrometry (LC/LC-MS/MS) is the state of the art. The main reasons are because it allows full system automation, less problems in repeatability, and adequate results in analysis of highly complex biological samples. Therefore, this dissertation developed the method LC/LC-MS/MS (modality on-line column switching), this has a cation exchange column (homemade), trap column to clean, hydrophobic capillary column and separation and detection by tandem mass spectrometry. We have proposed an improved analytical instrumentation, with a homemade trap that particles have high retention of peptide, which permit great recuperation of samples. Because it is an instrumental technique difficult, such as, obtain compatibility between the chromatography dimensions, can lose samples in the process and long time analysis, we have proposed a new optimization approach with chemometric analysis of data. On that, were evaluated twelve instrumental parameters and there was a simplification only two factors, these were responsible for 95% of greater response of method. As a result, the coverage of BSA protein was 82,54%, number of peptides 65 and score of 2134,05 values of high significance if compare from that there are in literature that presented greater time analysis. This work describes information about chemistry of peptides to method proposed through a surface of response and math equation that can contribute to different proteomes.
87

Avaliação da bioequivalência de formulações contendo lorazepam através de método bioanalítico utilizando a cromatografia líquida acoplada ao sistema de detecção por espectrometria de massa / A bioanalytical method using liquid chromatography coupled to MS/MS detection system for the quantification of Lorazepam in human plasma aiming bioequivalence studies.

Maurício Rocha de Magalhães Sampaio 17 April 2008 (has links)
Desenvolveu-se método de alta sensibilidade e especificidade por cromatografia liquida de alta eficiência acoplada a detecção por espectrometria de massas (LC-MS/MS) para quantificação do lorazepam em plasma humano visando aplicação em estudo de bioequivalência entre duas formulações de comprimidos contendo esse fármaco. A preparação das amostras de plasma foi feita por extração líquido-líquido usando hexano:diclorometano (60:40 v/v) como solvente de extração. O padrão interno usado foi o bromazepam. A separação cromatográfica ocorreu utilizando-se coluna analítica modelo Gemini® C18 110 A (150 mm x 4,6 mm; partículas de 5µm). Mistura de metanol e tampão acetato de amônio 10 mM (80:20, v/v), acrescida de 0,1% de ácido fórmico ao final da preparação, foi usada como fase móvel. A interface entre HPLC e MS/MS foi a fonte de ionização por eletrospray (ESI) operando em modo positivo (ES+). O analito e o PI foram monitorados e quantificados através de multiple reaction monitoring (MRM). As transições monitoradas foram m/z 320,69 > 274,96 para o lorazepam e m/z 318,00 > 182,20 para o padrão interno. O método foi validado na faixa de concentração de 0,50 a 80,0 ng/ml em plasma humano. A bioequivalência entre as formulações foi determinada através dos intervalos de confiança 90 % obtidos para as razões dos parâmetros farmacocinéticos Cmax (99% - 114%), AUC0-t (93% - 105%) e AUC0-inf (96% - 107%). Concluiu-se que as duas formulações podem ser administradas de maneira intercambiável sem prejuízo da eficácia terapêutica. / A method of liquid chromatography coupled to mass spectrometric detection (LC-MS/MS) with high sensitivity and specificity was developed to quantify Lorazepam in human plasma. This method was applied in a bioequivalence study between two tablet formulations. The preparation of plasma samples were performed by liquid-liquid extraction using hexanedichloromethane (60:40 v/v) as extraction solvent. The internal standard was bromoazepam. The chromatographic separation was achieved using the Gemini® C18 110A (150 mm x 4.6mm; 5µm particles) analytical column. The mobile phase was prepared from a mixture of methanol and 10mM of ammonium acetate (80:20, v/v), and finally adding 0.1% of formic acid. The HPLC and MS/MS interface was the electrospray ionization source (ESI), operating in positive mode (ESI+). The analyte and internal standard were monitored and quantified through multiple reaction monitoring (MRM). The monitored transitions were m/z 320.69 > 274.96 for lorazepam and m/z 318.00 > 182.20 for the internal standard. The method was validated over the range 0.50 to 80.0 ng/mL in human plasma. The bioequivalence between the two formulations was determined inside the 90% confidence interval for the pharmacokinetic parameters, Cmax (99% - 114%), AUC0-t (93% - 105%) and AUC0-inf (96% - 107%). It was concluded that the two formulations can be administered in an interchangeable manner without losing the therapeutic efficiency.
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Desenvolvimento de uma metodologia analítica  por LC-MS/MS para determinação de meta-clorofenilpiperazina em plasma de camundongos submetidos à privação de sono paradoxal / Development of an analytical methodology by LC-MS/MS for determination of meta-chlorophenylpiperazine in plasma of mice submitted to paradoxical sleep deprivation

Daniel Ninello Polesel 13 December 2012 (has links)
O aumento no uso abusivo e nas apreensões de comprimidos contendo 1-(3-clorofenil)piperazina (mCPP) têm sido observado na Europa desde o final do século 20. A mCPP promove efeitos semelhantes a metilenodioximetanfetamina (ecstasy) e surgiu como uma alternativa menos neurotóxica. Os principais efeitos descritos pelos usuários são sensação de bem-estar, euforia e empatia. Os efeitos adversos observados em casos de intoxicação aguda são a ansiedade, confusão, insônia, ataques de pânico, estados convulsivos, taquicardia e até mesmo a morte. A mCPP frequentemente tem seu uso associado com a privação de sono dos usuários em ambientes noturnos (festas e danceterias). Além disso, o fármaco provoca insônia no usuário, agravando ainda mais as consequências ao sono do indivíduo. O sono REM, em humanos, ou chamado de sono paradoxal nos animais, é uma fase importante do sono, por ser ela a fase de retorno da homeostasia comportamental e bioquímica. O objetivo deste trabalho foi avaliar os efeitos comportamentais dos isômeros da clorofenilpiperazina e desenvolver um método analítico para identificar e quantificar a mCPP em amostras de plasma de camundongos submetidos à privação de sono paradoxal (PSP) por 24 e 48 horas. A ferramenta analítica empregada para identificar e quantificar a mCPP foi a cromatografia líquida acoplada à espectrometria de massas (LC-MS/MS). As análises comportamentais de ansiedade e atividade locomotora dos camundongos utilizaram os testes do Labirinto em Cruz Elevado e o teste do Campo Aberto, respectivamente. Os resultados mostraram que a associação da PSP com o uso da mCPP acarretou mudanças comportamentais que voltaram ao nível homeostásico somente após 48 horas de rebote de sono. Além disso, observou-se um aumento significativo na concentração circulante de mCPP nos animais PSP por 48 horas em relação ao grupo controle. Por fim, concluiu-se que a privação de sono paradoxal associada com a administração da mCPP produziu graves consequências comportamentais em camundongos e que a concentração do fármaco encontrado no plasma foi maior nos animais submetidos à privação de sono paradoxal. / The increase on abusive use and seizures of tablets containing 1-(3-chlorophenyl)piperazine (mCPP) have been seen in Europe since the late 20th century. The mCPP promotes effects similar to methylenedioxymethamphetamine (ecstasy) and emerged as a less neurotoxic alternative. The main effects described by users are sense of well-being, euphoria and empathy. The adverse events observed in acute poisoning cases are anxiety, confusion, insomnia, panic attacks, convulsive states, tachycardia and even death. mCPP is often associated with sleep deprivation by their users and on night scenery (parties and discos). In addition, the drug causes insomnia on user, further aggravating the consequences to the individual sleep. REM sleep in humans or referred as to paradoxical sleep, in animals, is an important sleep phase, because it was the phase which promote the return of behavioral and biochemical homeostasis. The aim of this study was to evaluate the behavioral effects of the isomers of chlorophenylpiperazine and develop an analytical method to identify and quantify the mCPP in plasma samples from mice subjected to paradoxical sleep deprivation (PSD) for 24 and 48 hours. The analytical tool used to identify and quantify the mCPP was liquid chromatography coupled to mass spectrometry (LC-MS/MS). The behavioral analysis of anxiety and locomotor activity of mice used the Elevated Plus Maze and Open Field tests, respectively. The results showed that association of PSD with the use of mCPP led to behavioral changes that back to the homeostatic level only after 48 hours of rebound sleep. Furthermore, there was a significant increase in circulating concentration of mCPP in animals paradoxical sleep deprived for 48 hours compared to control group. Finally, it is concluded that paradoxical sleep deprivation associated with administration of mCPP produced severe behavioral effects in mice and concentration of drug found in plasma was greater in animals submitted to paradoxical sleep deprivation than control group.
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Fitohemijski skrining i procena antioksidantnog i antiinflamatornog potencijala sekundarnih biomolekula u vrstama roda Plantago L. / Phytochemical screening and evaluation of antioxidant and anti-inflammatory potential of secondary metabolites of Plantago L. species

Beara (Krstić) Ivana 09 July 2010 (has links)
<p>Karakterizacija metanolnih ekstrakata jedanaest vrsta samoniklih bokvica (rod<em> Plantago L.</em>) obuhvatala je fitohemijski skrining i ispitivanje antioksidantne i antiinflamatorne aktivnosti. Primenom LC-MS/MS tehnike odreĊen je sadržaj odabranih sekundarnih biomolekula. Antioksidantna aktivnosti ekstrakata (sposobnost neutralizacije slobodnih radikala, redukcioni potencijal i inhibicija lipidne peroksidacije) ispitana je primenom spektrofotometrijskih metoda. U cilju odreĊivanja antiinflamatornog potencijala, razvijena je<em> in vitro </em>metoda za praćenje aktivnosti trombocitne ciklooksigenaze-1 i 12-lipoksigenaze. Svi ispitani ekstrakti pokazali su znaĉajnu biolo&scaron;ku aktivnost.</p> / <p>Characterization of methanol extracts of eleven<em> Plantago L.</em> species included phytochemical screening and evaluation of antioxidant and anti-inflammatory activity. The content of several secondary metabolites was determined by LC-MS/MS technique. Antioxidant activity of extracts (radical scavenger capacity, reduction potential and inhibition of lipid peroxidation) was examined by spectrophotometric methods. With the intention to evaluate anti-inflammatory activity, an<em> in vitro method</em> was developed to measure activity of platelet cyclooxygenase-1 and 12-lipoxygenase. All examined extracts showed noticeable biological activity.</p>
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Identification of genetic, environmental and technologic factors associated to the variability of vitamins in common wheat and wheat based food products / Identification de facteurs génétiques, environnementaux et technologiques associés à la variabilité de la valeur nutritionnelle du blé et des produits industriels dérivés

Nurit, Eric 22 September 2015 (has links)
Le blé est la seconde céréale la plus cultivée dans le monde et constitue un apport majeur de l’alimentation quotidienne. L’effort consenti à continuellement améliorer les qualités meunière et boulangère du blé tendre, s’est fait au détriment du caractère nutritionnel du grain. Ainsi la plupart des produits industriels dérivés des grains de blé sont produits à partir de farines blanches raffinées qui ne contiennent ni le germe ni les sons. Cependant, dans ces différents tissus qui sont éliminés et qui servent essentiellement à nourrir les animaux, se concentrent les principaux micronutriments tels que les vitamines, les minéraux, les fibres et des substances phytochimiques. Les différentes enquêtes épidémiologiques ont bien mis en évidence les conséquences négatives de la déplétion en micronutriments des produits céréaliers raffinés. Dans l’objectif d’une alimentation plus saine voir même préventive, la consommation d’aliments enrichis en micronutriments naturellement présents dans le grain de blé tendre semble être une démarche efficace. Dans cette optique, ce travail de thèse a permis de consolider et d’accroitre les connaissances concernant les voies d’amélioration des teneurs en vitamines des grains de blés tendres ainsi que des produits industriels qui en sont dérivés. En premier, nous nous sommes intéressés au développement d’une méthode simple et rapide basée sur la spectrométrie de masse couplée à la chromatographie liquide pour la détermination simultanée de sept vitamines hydrosolubles dans divers matériels végétaux. Les vitamines présentes dans les différents matériels végétaux furent séparées en moins de 15 min grâce à l’utilisation d’une colonne C18 en phase inverse, et analysées en mode ElectroSpray positif et MRM. La réponse pour toutes les vitamines a été linéaire sur l’ensemble des concentrations étudiées (0.05 to 9 μg/mL) avec des coefficients de corrélation compris entre 0.991 et 1. Les limites de quantification de la méthode analytique ont été évaluées entre 0.09 et 3.5 μg/g. Les précisions intra-journalière et inter-journalière étaient satisfaisantes. La deuxième partie de nos travaux a concerné l’impact des procédés de transformation du grain (production d’une nouvelle fraction de mouture et grillage) sur la teneur en vitamines. Afin de réaliser cette objectif, la méthode développée a été appliquée pour l’analyse simultanée des concentrations en vitamines hydrosolubles contenues dans différentes farines semi-complètes ainsi que dans les pâtons, pains et pains grillés qui en sont dérivés. En parallèle, les concentrations endogènes des vitamines E, de la Lutéine et du β-sitostérol ont également été évaluées dans le même matériel. Nous avons mis en évidence que les concentrations en acide nicotinique, pyridoxale, pyridoxine et acide pantothénique étaient significativement plus élevées dans les gros sons que dans les autres fractions de moutures, alors que les concentrations en β-sitostérol, lutéine, α-tocotriénol, α-tocophérol et thiamine (20.87 μg/g DM)étaient plus importantes dans la fraction de mouture enrichie. L’étape de grillage induit une augmentation significative en α-tocophérol (+216%), β-γ-tocophérol (+52%), α-tocotriénol (+83%), β-γ-tocotriénol (+32%), acide nicotinique (+55%), nicotinamide (+97%) et en pyridoxine (+77%). L’ensemble de ces résultats nous a permis de montrer qu’un enrichissement de farine blanche par la fraction de mouture dite enrichie pourrait potentiellement permettre d’accroître les produits qui en dérive en vitamine E. De plus le grillage pourrait libérer des composés bioactifs, augmentant ainsi leur biodisponibilité et la valeur nutritionnelle des pains. (...) / Wheat is the second largest crop cultivated around the world and constitutes a major part of the daily diet in Europe. During the course of improving the baking quality of wheat cultivar, most of the nutritional attributes have been underestimated. It is therefore unfortunate that most of wheat-based food products are mostly produced from refined white flour from which peripheral tissues (germ and envelopes) are removed. However, these tissues, which are eliminated and serve mainly for animal feeding, contain most of the vitamins, minerals, fiber and phytochemicals of the grain. It is becoming evident that many of the health benefits associated with the consumption of whole grain cereal products, relate to the enhanced intake of micronutrients, phytochemicals and dietary fiber. In the context of consuming wheat derived foods with enhanced nutritional value, as part of a healthy diet, this thesis provide results which strengthen the knowledge of vitamins accumulation in common wheat and in wheat-based food products. Firstly, we have developed a simple and rapid method based on liquid chromatography tandem mass spectrometry (LC-MS/MS) for the simultaneous screening of seven water soluble vitamins in various wheat-based food materials. The vitamins present in the test materials were separated in less than 15 min by using a reverse-phase C18 column, and analyzed by positive ion electrospray selected reaction monitoring MS/MS. The MS response for all the vitamins was linear over the working range (0.05 to 9 μg/mL) with correlation coefficients ranging between 0.991 and 1. Limits of quantification in the different food materials ranged from 0.09 to 3.5 μg/g. Intra-day and inter-day precision was found satisfactory. The second part of our research, have focused on monitoring the levels of vitamins upon the wheat-based foods processing operations, such as production of new wheat milling fraction (consisting in enriched fraction) and breadmaking toasted bread. In order to achieve this goal, the developed method was applied for the simultaneous analysis of the water-soluble vitamin natural content of different semi-coarse wheat flours and in their corresponding baking products. In addition the vitamin E, Lutein and β-sitosterol natural content was also measured in the same materials. It was shown that the concentration of nicotinic acid, pyridoxal, pyridoxine, pantothenic acid were significantly higher in the coarse bran than in the other milling fractions, while the concentration of β-sitosterol, lutein, α-tocotrienol, α-tocopherol and thiamin (20.87 μg/g DM) were the highest in the enriched fraction. The toasting step induced a significant increased of α-tocopherol (+216%), β-γ-tocopherol (+52%), α-tocotrienol (+83%), β-γ-tocotrienol (+32%), nicotinic acid (+55%), nicotinamide (+97%) and of pyridoxine (+77%). Furthermore, it was demonstrated that the enriched fraction could be a functional ingredient in order to enrich wheat-based products in fat soluble vitamins and that the toasting process could release bound bioactive compounds and led to enhance the nutritional quality of bread. (...)

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