Devant la nécessité de préservation de l’environnement, la chimie devra de plus en plus devenir « verte ». Le développement de catalyseurs bio-hybrides est une voie prometteuse vers une chimie verte. En effet, ces catalyseurs combinent à la fois les avantages de la catalyse homogène (large gamme de réactivité) et ceux de la catalyse enzymatique (réaction en milieux aqueux, optimisation possible par génie biotechnologique). Ces nouveaux types de catalyseurs éco-compatibles semblent être à ce jour une alternative intéressante à la catalyse chimique classique.Cette thèse s’inscrit dans le cadre du développement de nouveaux catalyseurs bio-hybrides appelés Hémozymes, basés sur l’insertion non covalente de complexes métalliques hydrosolubles (responsables de l’activité catalytique), au sein d’une protéine hôte : la Xylanase A (pouvant induire une régio/stéréo/chimio-sélectivité).Pour cette étude, nous avons synthétisé différents complexes métalliques de taille variable (porphyrines, salens et salophens) métallés soit par du fer soit par du manganèse. L’étude de leur association avec la Xln A ainsi que les essais de leur activité catalytique nous ont permis d’aboutir à des résultats intéressants, d’une part pour la réaction d’oxydation du thionanisole par le peroxyde d’hydrogène, d’autre part pour l’oxydation d’alcènes aromatiques par l’oxone (KHSO5). Nous avons ainsi obtenu deux métalloenzymes artificielles remarquables, l’une capable de catalyser l’oxydation énantiosélective du thioanisole par le peroxyde d’hydrogène (84% de rendement, 40% d’excès énantiomérique en faveur de l’isomère S), l’autre capable de catalyser l’époxydation asymétrique du paraméthoxy-styrène par KHSO5 (17% de rendement, 80% d’excès énantiomérique en faveur de l’isomère R). Enfin, de nouvelles stratégies pour concevoir des catalyseurs bio-hybrides ont également été envisagée comme le greffage covalent de complexes métalliques au sein d’une protéine hôte, ou encore l’utilisation d’une forte affinité ligand-protéine (comme les interactions de type inhibiteur) pour enfouir un cofacteur métallique au sein d’une protéine. / In those days, the preservation of the environment is a huge challenge, so chemistry has to become more "Green". The development of bio-hybrid catalysts is a promising way towards a green chemistry. Indeed, these catalysts both combine the benefits of homogeneous Catalysis (wide range of reactivity) and those of enzyme catalysis (reaction in aqueous media, possible optimization by biotechnological engineering). These new kind of eco-compatible catalyst seem to be an interesting alternative to classical chemical catalysis to this day.For this study, we have synthesized various complexes with various size (porphyrins, salens and salophens) metalled by iron or manganese. The study of their association with Xln A and the catalytic activity assays allowed us to achieve interesting results, on the one hand to the oxidation of the thionanisole by hydrogen peroxide, on the other hand for the oxidation of aromatic alkenes by the oxone (KHSO5).This thesis is about the development of new bio-hybrid catalysts called Hemozymes, based on the non-covalent insertion of water-soluble metal complexes (responsible for the catalytic activity), inside a host protein: Xylanase A (which can induce a regio/stereo/chemo-selectivity).We have thus obtained two remarkable artificial metalloenzymes, one able to catalyze the enantioselective oxidation of thioanisole by hydrogen peroxide (84% yield, 40% of enantiomeric excess for the S isomer), the other able to catalyze the asymmetric epoxidation of paramethoxy-styrene by KHSO5 (17% yield, 80% enantiomeric excess for the R isomerFinally, new strategies to develop bio-hybrid catalysts have also been considered, such as covalent linkage of metal complexes within a host protein or the use of a high ligand-protein affinity (such as the interactions of inhibitor with proteins) to introduce the metal cofactor inside the protein pocket.

Made available in DSpace on 2015-04-22T22:02:02Z (GMT). No. of bitstreams: 1 DISSERTACAO-CLEUTON DE SOUZA SILVA.pdf: 1557616 bytes, checksum: c0477dc397214e5783a5d2ca234ee08a (MD5) Previous issue date: 2009-01-14 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This work presents a theoretical study and modeling of the metal-porphyrins monomers and the search of the porphyrin-metal complexes that can act as a potential catalyst to make the cleavage of the O2 bond for use in fuel cell. All calculations were made by the Gaussian package on the Windows OS, using the DFT, by the B3LYP functional, and the 6-31G and LANL2DZ basis set. The studied porphyrin-metal complexes were those formed by the porphyrin ring and the Si, Ni, Ge, Co, Fe, Mo and Sn metals in the different oxidation states. The obtained theoretical model was satisfactory for the description of role played by the metal-porphyrins complexes in the catalysis of the O2 molecule. In the obtained model, the porphyrin-metal- complexes showed the capability of aggregate the O2 molecules and weaken the strength of this chemical bond facilitating the final reduction process in the catalyst. In general, although not acting as a catalyst in the oxygen reduction reaction (o.r.r.), can be observed the importance of the porphyrin ring to a possible use in PEM fuel cell, that is, facilitating the catalysis process in the latter step of the reaction process. / Este trabalho apresenta uma modelagem teórica de monômeros de metaloporfirinas e a busca de metais para o núcleo porfirínico que apresentem o melhor potencial como catalisadores para a quebra da ligação O-O para aplicação em células a combustível. Os cálculos foram realizados em plataforma de Windows, através do pacote GaussianTM 2003, utilizando abordagem da Teoria do Funcional de Densidade (DFT) e o uso do funcional b3lyp com bases de 3-21G, 6-31G e lanl2dz. As porfirinas estudas foram Si+4-porfirina, Si+2-porfirina, Ni+2-porfirina, Ge+2-porfirina, Co+2-porfirina, Co+3-porfirina, Fe+2-porfirina, Mo+6-porfirina e Sn+2-porfirina. O modelo químico-quântico adotado mostrou-se satisfatório para descrição da atuação das metaloporfirinas na catálise do O2, mostrando que as metaloporfirinas podem auxiliar no processo eletroquímico, uma vez que os resultados mostram que todas podem ser capazes de agregar as moléculas de O2, enfraquecendo a ligação O-O para posterior redução num catalisador. No geral, embora não atuando como catalisador da r.r.o., pôde-se observar a importância do macrociclo porfirínico para uma possível atuação em células a combustível do tipo PEM, ou seja, facilitando a catálise numa etapa posterior do processo reacional.

Este estudo relata a síntese dos catalisadores heterogêneos Fe3O4@nSiO2@MCM-41-MnP e Fe3O4@nSiO2@MCM-41(E)-MnP. São sistemas que aliam as propriedades catalíticas de metaloporfirinas, com as propriedades magnéticas das nanopartículas de magnetita (Fe3O4) numa matriz estruturada de sílica mesoporosa MCM-41. A síntese das nanopartículas de Fe3O4 foi seguida pelo revestimento de sua superfície com camada fina de sílica (Fe3O4@nSiO2). Em seguida, a estrutura mesoporosa da sílica MCM-41 foi formada sobre as partículas recobertas na presença de brometo de hexadeciltrimetilamônio, como surfatante, e tetraetilortosilicato, como o precursor de sílica, obtendo-se o compósito Fe3O4@nSiO2@MCM-41. No processo de síntese do compósito Fe3O4@nSiO2@MCM-41(E), o mesitileno foi incorporado como agente expansor de estrutura, a fim de se obter poros com diâmetros maiores que os característicos para a sílica mesoporosa MCM-41. Os compósitos foram funcionalizados com o agente sililante 3-aminopropiltrietoxisilano. Esta etapa permitiu a imobilização covalente da [Mn(TF5PP)]Cl nos compósitos através de uma reação de substituição nucleofílica aromática, gerando os catalisadores Fe3O4@nSiO2@MCM-41-MnP e Fe3O4@nSiO2@MCM-41(E)-MnP. Caracterizações por espectroscopia no ultravioleta-visível e no infravermelho, reflectância difusa no UV-Vis, magnetometria de amostra vibrante, difração de raios-X, microscopia eletrônica de varredura e transmissão e isotermas de adsorção-dessorção de N2, permitiram compreender a estrutura e morfologia dos catalisadores. A atividade catalítica dos sistemas na oxidação de hidrocarbonetos ((Z) ciclo-octeno e ciclo-hexano) e na oxidação de fármaco (mirtazapina) foi avaliada; iodosilbenzeno ou ácido meta-cloroperoxibenzóico, foram utilizados como agente doador de oxigênio. Os testes catalíticos com os hidrocarbonetos demonstraram maiores rendimentos de epóxido para o catalisador Fe3O4@nSiO2@MCM-41(E)-MnP do que o catalisador Fe3O4@nSiO2@MCM-41-MnP. Estes rendimentos altos para o primeiro foram atribuídos ao seu maior tamanho de poros. Ambos os catalisadores foram seletivos para o produto ciclo-hexanol, indicando um comportamento biomimético. A oxidação do fármaco, nas condições deste estudo preliminar, gerou um metabólito que difere dos dois principais metabólitos (8-hidroximirtazapina e demetilmirtazapina) obtidos em estudos com enzimas P450. Estudos controle de oxidação do fármaco com manganês porfirina em solução revelaram que este sistema foi seletivo para formação do produto demetilmirtazapina. / This study reports on the preparation of the Fe3O4@nSiO2@MCM-41-MnP and Fe3O4@nSiO2@MCM-41(E)-MnP heterogeneous catalysts. They are systems that allies the catalytic properties of metalloporphyrins with the magnetic properties of magnetite (Fe3O4) nanoparticles in a structured matrix of MCM-41 mesoporous silica. Synthesis of Fe3O4 nanoparticles was followed by surface coating with a thin silica layer (Fe3O4@nSiO2). Then, a MCM-41-type mesoporous silica structure was grown over the coated particles in the presence of hexadecyltrimethylammonium bromide, as surfactant, and tetraethylorthosilicate, as the silica precursor, to yield the Fe3O4@nSiO2@MCM-41 composite. It was incorporated into the synthesis route of Fe3O4@nSiO2@MCM-41(E) composite the mesitylene as expanding agent structure, in order to obtain pores with diameters greater than the characteristic for the MCM-41 mesoporous silica. The resulting composites was functionalized with the silylating agent 3-aminopropyltriethoxysilane. This enabled covalent immobilization of [Mn(TF5PP)]Cl onto the composite via a nucleophilic aromatic substitution reaction, to afford the Fe3O4@nSiO2@MCM-41-MnP and Fe3O4@nSiO2@MCM-41(E)-MnP catalysts. Characterization of the catalysts by ultraviolet-visible and infrared spectroscopies, UV-Vis diffuse reflectance, vibrating sample magnetometer, X-ray diffractometry, scanning and transmission electron microscopies and N2 adsorption-desorption isotherm, aimed to understand the structure and morphology of the catalysts. The catalytic activity of the systems in hydrocarbon oxidation ((Z)-cyclooctene and cyclohexane) and the drug oxidation (mirtazapine) was evaluated; iodosylbenzene or meta-chloroperoxybenzoic acid, were used as the oxygen donor agent. The catalytic tests with the hydrocarbons demonstrated higher yields of epoxide for Fe3O4@nSiO2@MCM-41(E)-MnP than Fe3O4@nSiO2@MCM-41-MnP catalyst. These high yields for the first catalyst, were attributed to larger pore size. Both catalysts were selective for the cyclohexanol product, indicating a biomimetic behavior. The drug oxidation, under the preliminary study conditions, generated a metabolite that differs from the two major metabolites (8-hydroxy mirtazapine and demethylmirtazapine) obtained in studies with P450 enzymes. Control drug oxidation studies with manganese porphyrin solution revealed that this system was selective for formation of demethylmirtazapine product.

Neste trabalho foram estudadas a atividade catalítica de metaloporfirinas e complexos salen (catalisador de Jacobsen), em solução e imobilizados em diferentes suportes, na oxidação de hidrocarbonetos e fármacos anticonvulsivantes (carbamazepina e primidona) e antidepressivo (fluoxetina), utilizando os seguintes doadores de oxigênio: peróxido de hidrogênio, terc-butil hidroperóxido (t-BOOH), ácido m-cloroperbenzóico (m-CPBA) e iodosilbenzeno (PhIO). Os catalisadores contendo o complexo salen imobilizado em alumina, membranas de quitosana e membranas polidimetilssiloxano/acetato de polivinila (PDMS/PVA), foram preparados e caracterizados por espectroscopia UV-Vis, análise termogravimétrica, calorimetria exploratória diferencial, análise térmica diferencial, infravermelho, microscopia eletrônica de varredura, raios-X e área superficial. Foi investigada a atividade destes materiais inicialmente na catálise oxidativa de hidrocarbonetos (cicloocteno, estireno e cicloexano). Estes sistemas heterogêneos se mostraram bastante eficientes para oxidação destes substratos, com rendimentos de até 79 % de ciclooctenóxido e elevada seletividade para formação de epóxido ou cetona, quando se utilizam os substratos alcenos ou cicloexano, respectivamente. As membranas de quitosana e membranas híbridas PDMS/PVA foram avaliadas em sistema trifásico, nos quais a membrana se localiza na interface entre a fase apolar (substrato orgânico) e a fase aquosa (contendo o oxidante). Os resultados catalíticos foram excelentes, obtendo-se freqüências de turnovers da ordem de 138 h-1. As reações de oxidação dos fármacos (carbamazepina, primidona e fluoxetina) foram analisadas por cromatografia líquida de alta eficiência (CLAE-UV) em fase reversa, por cromatografia líquida acoplada a espectrometria de massas (LC-ESI) e cromatografia gasosa acoplada à espectrometria de massas (CG-MS), para identificação dos produtos. Na oxidação da carbamazepina (CBZ) foi produzido apenas o 10,11-epóxido-carbamazepina (CBZ-EP), que corresponde ao principal metabólito obtido no metabolismo in vivo catalisado pelo P450, indicando que os sistemas catalíticos utilizados são excelentes modelos biomiméticos desta enzima. Observou-se que a formação de CBZ-EP é dependente do oxidante e do pH do meio, principalmente nas reações com peróxido de hidrogênio, resultando em mecanismos de clivagem homolítica ou heterolítica conforme o pH da reação. Os oxidantes m-CPBA e t-BOOH mostraram que a natureza dos substituintes ligados ao grupo OOH do peróxido exerce grande efeito na oxidação da CBZ. Na oxidação da primidona foram obtidos dois metabólitos encontrados no sistema in vivo: feniletilmalonamida e fenobarbital, além de três outros produtos (2-fenilbutiramida, -fenil--butirolactona e um produto em nível de traços, não identificado). A formação destes compostos foi altamente dependente do oxidante, co-catalisador, pH e oxigênio, o que possibilitou a proposta de um esquema de oxidação com os possíveis intermediários envolvidos. Todos os sistemas catalíticos utilizados na oxidação da fluoxetina estudados geraram o produto de N-desalquilação, o p-trifluorometilfenol (TFMF). A norfluoxetina principal metabólito deste fármaco in vivo, resultante de N-desmetilação, não foi produzida, indicando que a reação de O-desalquilação prevalece e, portanto, os catalisadores não seguem a rota biomimética para este fármaco. Este trabalho demonstrou a habilidade do complexo salen e das metaloporfirinas para mimetizar a ação do citocromo P450 na oxidação de fármacos. Os resultados mostram também o grande potencial de aplicação de modelos biomiméticos para sintetizar metabólitos e fornecer amostras para testes farmacológicos e toxicológicos, visando elucidação do metabolismo do fármacos, e como uma alternativa aos estudos enzimáticos. / In this work, the catalytic activities of metalloporphyrins and the salen complex (Jacobsen catalyst) in solution and immobilized on different supports were studied in the oxidation of hydrocarbons, anticonvulsivant drugs (carbamazepine and primidone) and antidepressives (fluoxetine) by the following oxygen donors: hydrogen peroxide, terc-butyl hydroperoxide (t-BOOH), 3-chloroperoxybenzoic acid (m-CPBA), and iodosylbenzene (PhIO). The catalysts containing the salen complex immobilized on alumina, chitosan membranes and poly(dimethylsiloxane)/polyvinyl acetate membranes (PDMS/PVA) were prepared and characterized by UV-Vis spectroscopy, thermogravimetric analysis, differential thermal analysis, differential scanning calorimetry, infrared spectroscopy, scanning electron microscopy, X-ray diffraction, and surface area analysis. The activity of these materials was initially investigated in the oxidative catalysis of hydrocarbons (cyclooctene, styrene and cyclohexane). These heterogeneous systems were efficient for the oxidation of these substrates, with yields as high as 79 % for cyclooctene oxide. The selectivity for epoxide or ketone formation was high when the substrate alkenes or cyclohexane were used, respectively. The chitosan membranes and hybrid membranes PDMS/PVA were available in a triphasic system, where the membrane was located in the interface between the apolar phase (organic substrate) and the aqueous phase (containing the oxidant). The catalytic results were excellent, with turnover frequencies of 138 h-1. Drug oxidation (carbamazepine, primidone and fluoxetine) products were analyzed by High Performance Liquid Chromatography (HPLC-UV) in reverse phase, liquid chromatography coupled to mass spectrometry (LC-ESI), and gas chromatography coupled to mass spectrometry (GC-MS), for products identification. In the case of carbamazepine (CBZ) oxidation only carbamazepine 10,11- epoxide (CBZ-EP) was produced. This is to the main metabolite obtained in carbamazepine metabolism by P450 in vivo, indicating that the catalytic systems employed here are excellent biomimetic models of this enzyme. Formation of CBZEP is highly dependent on the oxidant and pH, especially in the reaction with hydrogen peroxide, resulting in homolytic and/or heterolytic cleavage, according to the pH of the reaction medium. The oxidants m-CPBA and t-BOOH showed that the presence of substituents linked to the -OOH group of the peroxide affects the catalytic activity of the studied system significantly. As for primidone oxidation, two metabolites found in the in vivo system were obtained: phenylethylmalondiamide and phenobarbital, besides three other products (2-phenylbutyramide, g-phenyl-g-butyrolactone and, a product in trace amounts, not identified). The formation of these compounds was highly dependent on the oxidant, co-catalyst, pH and presence of oxygen. These results enabled the proposition of a scheme for Mn(salen)-catalyzed primidone oxidation and the possible intermediate involved. All the studied catalytic systems used in fluoxetine oxidation generated the product obtained via the O-dealkylation mechanism, p-trifluoromethylphenol (TFMF). Norfluoxetine, the main metabolite in vivo and formed via the N-demethylation mechanism, was not obtained. This indicates that the O-dealkylation mechanism prevails and, therefore, the catalysts do not follow the biomimetical route in the case of this drug. This work demonstrated the ability of the salen complex and metalloporphyrins to mimic the action of cytochrome P450 in drug oxidation. These results showed the potential application of these biomimetic models in the synthesis of drug metabolites, which should provide samples for pharmacological and toxicological tests, as well as aid studies that pursue the elucidation of in vivo drug metabolism, being an alternative to enzymatic studies.

As neolignanas, bem como as lignanas, apresentam diversas atividades biológicas comprovadas, sendo a licarina A uma neolignana diidrobenzofurânica, detentora de atividade leishmanicida. A partir dessa atividade e do interesse na produção de fármacos eficazes no tratamento dessa doença, a licarina A foi selecionada para estudo de metabolismo in vitro a partir de reações biomiméticas utililizando [Fe(TPP)Cl] e Mn(Salen) como catalisadores; sob ação de oxidantes (PhIO e mCPBA) em quatro solventes de polaridades distintas (AcOEt, MeOH, ACN, DCM), na proporção de 1:30:30 (catalisador:substrato:oxidante). Inicialmente, as reações realizadas foram submetidas às análises por CG-EM comprovando um produto de oxidação majoritário m/z 342, denominado metabólito A. Os solventes de menor polaridade (DCM e AcOEt), bem como o catalisador de Jacobsen, foram mais eficientes na geração desse metabólito. O aumento do tempo reacional bem como o aumento da concentração do oxidante não favoreceu a produção de metabólitos. Posteriormente, as análises dessas reações também foram realizadas por CLUE-DAD-EM/EM e sete metabólitos puderam ser identificados a partir do auxílio do estudo de fragmentação da licarina A bem como a partir de análises de RMN e EM dos metabólitos isolados por CLAE em escala semipreparativa. As análises de RMN dessas frações permitiram a determinação estrutural de um metabólito de m/z 343 [M+H]+ (metabólito 3) constituído de uma epoxidação nos carbonos C-7\'/C-8\' situados na cadeia lateral da licarina A. Sendo assim, quatro dos sete metabólitos (2, 3, 6 e 7) formados apresentaram m/z 343 [M+H]+ e espectros de massas tandem muito semelhantes, correspondendo aos possíveis diasteroisômeros do metabólito epoxidado, visto que a licarina A apresenta dois centros quirais. Outros três metabólitos foram produzidos e exibiram íons de m/z 361 [M+H]+, m/z 315 [M+H]+ e m/z 341 [M+H]+, correspondentes respectivamente a um diol vicinal em C-7\'/C-8\', um aldeído benzóico e um outro aldeído gerado a partir da oxidação da metila terminal em C-9\'. Foi realizado ainda o estudo de metabolismo in vitro com microssomas hepáticos de ratos, sendo que esse estudo foi capaz de reproduzir as reações biomiméticas a partir da produção do mesmo metabólito (2) (apresentando mesmo TR e mesmo espectro de UV). Em relação à toxicidade e aos possíveis danos que a licarina A poderia acarretar, um estudo de toxicidade aguda foi realizado sendo esse capaz de auxiliar na classificação da licarina A, sendo a mesma tóxica em doses > 300mg/kg e 2000mg/kg (categoria 4). Análises dos parâmetros bioquímicos realizadas foram capazes de determinar possível toxicidade hepática, a partir das alterações enzimáticas (AST, ALT, LDH, ALP) ocorridas. Contudo, análise microscópica de cortes dos tecidos (fígado, coração e rins) não determinaram nenhum comprometimento tecidual que pudesse evidenciar toxicidade. / Neolignans and lignans show several biological activities. Licarin A is a dihydrobenzofuranic neolignan, which exhibits leishmanicidal activity. For this reason, licarina A was selected to carry out the studies of in vitro metabolism. So biomimetic reactions were done by the use of [Fe(TPP)Cl] and Mn (Salen) catalysts, different oxidants (PhIO and mCPBA), as well solvents with different polarities (EtOAc, MeOH, ACN, and DCM), and the ratio of 1:30:30 (catalyst:substrate:oxidant). Initially, the reactions were analyzed by GC-MS and showed one major oxidation product of m/z 342 (metabolite A). The less polar solvents (DCM and EtOAc) and Jacobsen catalyst (Mn (Salen)) were more efficient for the production of metabolite A. The reaction time and concentration were increased, but they did not represent a higher production of metabolites. Subsequently these reactions were also analyzed by UPLC-DADMS/ MS and seven metabolites could be identified based on the fragmentation pattern proposed for licarin A, as well as from NMR and MS data of the metabolites isolated by HPLC. A metabolite of m/z 343 [M+H]+ (metabolite 3) was identified by NMR and MS/MS data and it consists of epoxidation in the carbons of C-7\'/C-8\' from licarin A. Therefore, four of the seven metabolites (2, 3, 6 and 7) exhibited m/z 343 [M+H]+ in the MS spectra and the MS/MS showed high similarity with the epoxided metabolite (metabolite 3). So these metabolites could be diasteroisomers of the metabolite 3. Three other metabolites were produced and exhibited ions at m/z 361 [M+H]+, m/z 315 [M+H]+ and m/z 341 [M+H]+, corresponding respectively to a vicinal diol in C-7\'/C-8\', benzylic aldehyde and other aldehyde generated from the oxidation of the terminal methyl at C-9\'. The study of in vitro metabolism by rat liver microsomes was also carried out, and this study was able to reproduce the biomimetic reactions by production of the same metabolite (2). The acute toxicity and potential damage of licarin A were evaluated and the results indicated toxicity for this compound at doses >300mg/kg and 2000mg/kg (category 4). Analysis of biochemical parameters were able to determine possible liver toxicity caused by enzymatic changes (AST, ALT, LDH, ALP). However, microscopic analysis of tissues sections (liver, heart and kidneys) did not show any tissue damage that could indicate toxicity.

La conception et le développement de biocapteurs pour la détection directe de biomarqueurs dans un échantillon de fluide biologique constituent un véritable défi dans la recherche pour leur application dans le système de point de soins en diagnostic. Mon projet est axé sur l'élaboration d'une nouvelle plateforme de décomposition biologique composée de graphène qui présente une surface électroactive et spécifique élevée permettant de greffer de nombreux biomolécules avec des métalloporphyrines en tant que nouveau marqueur redox pour suivre le processus de reconnaissance biologique obtenu dans le cas d'un capteur d'ADN. Le concept sera de démontrer que les métalloporphyrines où le potentiel d'oxydo-réduction pourrait être contrôlé par la nature des ions métalliques pourraient être appliquées dans une plate-forme de biocapteurs électrochimique multidétection. L'association de la métalloporphyrine avec le graphène offrira de nombreux avantages, comme la promotion de la réaction de transfert d'électrons et ayant une grande surface pour l'immobilisation des protéines. La détection de la cible présente sera réalisée suite à l'activité redox des métalloporphyrines greffées à la surface. Nous avons déjà synthétisé différentes métalloporphyrines modifiées et caractérisées par des techniques habituelles de spectrométrie telles que la RMN, les UV et la MS. Le biocapteur d'ADN a été construit par le composite de graphène et métalloporphyrine et sonde d'ADN comme biorécepteur suivant l'approche d'attachement covalent et l'optimisation de la construction de biocapteur pour améliorer la stabilité et la reproductibilité. Et nous avons déjà fait une détection de l'ADN cible par diverses méthodes électrochimiques, y compris la voltamétrie cyclique, la voltampérométrie à onde carrée et la spectroscopie d'impédance. Cette stratégie a été réalisée d'abord avec la porphyrine Mn insérée puis généralisée à divers complexes métalliques pour une approche multidétection. Parallèlement, les nanomatériaux hybrides combinant les caractéristiques du graphène (haute conductivité et grande surface spécifique) et des porphyrines (propriétés physiques et chimiques et capacité de transfert d'électrons), tels que la tétraphénylporphyrine portant un et quatre groupes carboxyliques nommés H₂TPP-nCP (n = 1, 4) et la tétraphénylporphyrine incorporant du manganèse (III) (MnTPP-1CP) ont été synthétisés avec succès. L'interaction entre H₂TPP-nCP (n = 1, 4) et l'oxyde de graphène chimiquement réduit (CRGO) a été étudiée dans mon travail de thèse. Pour étudier les propriétés caractéristiques des nanomatériaux préparés, la microscopie électronique à balayage (MEB), la microscopie à force atomique (AFM), les spectres UV-visible, les spectres infrarouges à transformée de Fourier (FT-IR) et les spectres de photoélectrons X. Afin d'éliminer l'absorption non spécifique, la modification de l'électrode par le PEA a également été appliquée et obtenir une excellente application pour la détection de la cible d'ADN. / The design and development of biosensors for direct detection of biomarkers in biological fluid sample is real challenge in research for their application in point of care system in diagnostic. My project is focus on the elaboration of a new platform for biological detaction composed of graphene which exhibits a high electroactive and specific surface suitable for grafting numerous biomoleculer with metalloporphyrins as a novel redox marker for following biological recognition process obtained in the case of DNA sensor. The concept will be to demonstrate that the metaloporphyrines where there redox potential could be controlled by the nature of metal ions could be applied in multidetection electrochemical biosensor platform. The association of metalloporphyrin with graphene will offer numerous advantages, as promoting electron transfer reaction and having a large surface for protein immobilization. The detection of target present will be performed following redox activity of the metalloporphyrins grafted on the surface. We have already synthesized various modified metalloporphyrins and characterizatized by usual spectrometry techniques such as NMR, UV and MS. The DNA biosensor has been constructed by the composite of graphene and metalloporphyrin and DNA probe as bioreceptor following covalent attachment approach and optimization of the biosensor construction for improving stability and reproducibility. And we have already done some detection of DNA Target by various electrochemical methods including cyclic voltammetry, square wave voltammetry and impedance spectroscopy. This strategy was performed firstly with on Mn inserted porphyrin and then generalized to various metal complex for multidetection approach. Meanwhile, the hybrid nanomaterials which combined the features of both graphene (high conductivity and large specific surface area) and porphyrins (physical and chemical properties and electron transfer ability), such as tetraphenylporphyrin bearing one and four carboxylic group named H₂TPP-nCP(n=1, 4) and tetraphenylporphyrin incorporating manganese (III) (MnTPP-1CP) were successfully synthesized. The interaction modes between H₂TPP-nCP(n=1, 4) and chemically reduced graphene oxide (CRGO) was studied in my thesis work. To investigate the characteristic properties of as-prepared nanomaterials, scanning electron microscopy (SEM), atomic force microscopy (AFM), UV-visible spectra, Fourier Transform infrared spectra (FT-IR), X-ray photoelectron spectra (XPS). In order to eliminate the non-specific absorption, the modification of the electrode by monolayer PEA was also applied and obtain excellent application for the detection of DNA target.

No description available.

As metaloporfirinas (MeP) cloreto de 5,10,15,20-tetra(pentafluorofenill)porfirina de manganês (III) e ferro (III) (MnIIIP e FeIIIP) foram imobilizadas em matriz de sílica híbrida mesoporosa do tipo SBA-15. Os grupos silanóis da SBA-15 foram modificados com (3-aminopropil)trietoxissilano (APTES) e (3-aminopropil)dietoximetilsilano (APDES), que após a imobilização das metaloporfirinas geraram os catalisadores FeP-APSBA, FeP-APMSBA, MnP-APSBA e MnP-APMSBA. Um terceiro tipo de material foi preparado a partir da ligação de grupos trimetilsilil (TMS) nos catalisadores FeP-APSBA e MnP-APSBA, gerando outros dois catalisadores que foram denominados FeP-APSBA-TMS e MnP-APSBA-TMS. Os materiais foram caracterizados por FTIR, RD UV-Vis, TG/TGA MEV, MET e isotermas de adsorção e dessorção de N2 (BET/BJH). Para analisar a natureza da interação solvente-superfície nos materiais, foram determinadas medidas goniométricas de energia livre de superfície. Os catalisadores foram estudados na oxidação dos substratos (Z)-ciclo-octeno e ciclo-hexano, utilizando iodosilbenzeno (PhIO) como espécie doadora de oxigênio a fim de avalia-los como biomiméticos do citocromo P450. Os parâmetros estruturais foram comparados aos resultados catalíticos frente à formação da gaiola de solvente e das espécies intermediárias de alta valência, FeIV(O)P+. e MnV(O)P e estudar como esses fatores afetam o rendimento e a seletividade das reações catalisadas. As MeP-SBAs apresentaram uma faixa de rendimento de 88 a 47 % para epoxidação de (Z)-ciclo-octeno. Já na oxidação de ciclo-hexano houve formação de 2 a 8 % de ciclo-hexanol e 2 % de ciclo-hexanona. Observou-se maior seletividade para o álcool com as FeP-SBAs. / Manganese (III) and iron (III) 5,10,15,20- tetra(pentafluorophenyl) porphyrin (MnIIIP and FeIIIP ) chloride were immobilized in mesoporous silica hybrid matrix SBA-15. Silanol groups were modified with (3-aminopropyl)triethoxysilane (APTES) and (3-aminopropyl)diethoxymethylsilane (APDES), generating catalysts called FeP-APSBA, FeP-APMSBA, MnP-APSBA and MnP-APMSBA. A third type of material was prepared from the binding trimethylsilyl groups (TMS) in FeP-APSBA and MnP- APSBA catalysts generating the other two catalysts named FeP-APSBA-TMS and MnP-APSBA-TMS. The materials were characterized by FTIR , DR UV-Vis , TG/TGA SEM , TEM and adsorption and desorption isotherms of N2 (BET/BJH) and to analyze the materials solvent - surface interaction nature the were determined goniometric measurements of surface free energy. Catalysts were evaluated for (Z)- cyclooctene and cyclohexane oxidation mediated by iodosylbenzene (PhIO) as the oxygen donor species to evaluate their catalytic activity as cytochrome P450 biomimetics. Structural parameters were compared to catalytic results related to cage solvent formation and the intermediate species high valence FeIV(O)P+. and MnV(O) P and how these factors affect the yield and selectivity of catalysts. MeP-SBA\'s reactions showed a range of 88-47 % for epoxidation (Z)-cyclooctene and cyclohexane oxidation yielding 2 to 8 % of cyclohexanol and 2 % of cyclohexanone. In the latter case was observed a higher selectivity for alcohol with FeP-SBA\'s.

Une nouvelle famille de porphyrines chirales bridées a été mise au point dans le but d'accéder à des systèmes présentant un processus redox irréversible, lié à une bistabilité conformationnelle, dans le but de les appliquer dans le domaine des mémoires moléculaires. Ces nouvelles porphyrines sont constituées de deux brides ancrées sur les quatre positions meso par des groupes cyclohexyle. Une amine secondaire a été insérée au centre des brides dans le but d'obtenir des métalloporphyrines présentant une seule conformation à l'équilibre pour une longueur de bride, un métal et un degré d'oxydation donnés et pour favoriser un changement conformationnel en fonction du degré d'oxydation d'un métal comme le manganèse. Pour cela, une nouvelle voie de synthèse des porphyrines bridées par pré-fonctionnalisation du dialdéhyde autour de la fonction amine a été conçue. Les porphyrines ont été caractérisées par spectroscopie RMN, spectroscopie UV-Visible et dichroïsme circulaire. Les conformations des bases libres, des complexes de zinc(II) et de nickel(II) ont été déterminées par RMN proton. Pour une longueur de bride de 9 atomes avec une amine secondaire, les conformations des complexes de zinc(II) et de nickel(II) sont respectivement αααα et ααββ. En partant de ce modèle, les complexes de manganèse(II) et de chloromanganèse(III) ont été synthétisés et caractérisés par spectroscopie UV-Visible, dichroïsme circulaire et RMN du carbone 13 afin d'étudier si des changements de conformation en fonction du degré d'oxydation du métal ont lieu. / A new family of chiral bridled porphyrins was designed in order to access systems presenting an irreversible redox process linked to a conformational switch. Such systems could be of high interest in the field of molecular memories. These new porphyrins are made of two bridles anchored to the four macrocycle meso positions through cyclohexyl groups. The first objective is to introduce a secondary amine in the centre of the bridles in order to allow metalloporphyrins with defined bridle length and specific metal with a given oxidation degree to be only under one conformation at equilibrium. The second objective is to favor a conformational switch dependent on the oxidation state of a redox metal such as manganese. To reach these goals, a new porphyrin synthetic pathway was established. The key steps of this new protocol were the synthesis of the bridle built around the central amine with two terminal aldehyde functions required for the macrocyle formation. Porphyrins were studied by NMR, UV-Visible and circular dichroism spectroscopies. The conformations of free base porphyrins, zinc(II) complexes and nickel(II) complexes were determined by 1H NMR. For a bridle with a chain length of 9 atoms including the secondary amine, the zinc(II) complex presents only an αααα conformation and nickel(II) complex an ααββ conformation. From these structural models, manganese(II) and chloromanganese(III) complexes were synthesised and characterised by UV-Visible spectroscopy, circular dichroism and 13C NMR in order to study the possible conformational switches dependent on the Mn redox state.

Orientador: Maria Aparecida Carvalho de Medeiros / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Tecnologia / Made available in DSpace on 2018-08-17T21:31:10Z (GMT). No. of bitstreams: 1 Santos_FlaviaFerreiradeSouzados_M.pdf: 3188351 bytes, checksum: 5ae9b978a432ed1f2c74038ebd5c9e43 (MD5) Previous issue date: 2011 / Resumo: Os resíduos químicos gerados em laboratórios de universidades são complexos devido a grande diversidade dos processos de geração e dos compostos que os constituem. Dessa forma, há necessidade de um plano de gestão para evitar que esses resíduos de composição diversificada sejam dispostos inadequadamente no meio ambiente. Nesse contexto encontra-se em implantação o Plano de Gestão de Resíduos Químicos (PGRQ) dos Laboratórios de Ensino e Pesquisa da Faculdade de Tecnologia - FT/UNICAMP. Com a finalidade de contribuir para a implantação do PGRQ da FT, o presente projeto visou realizar ações de gestão, tais como o diagnóstico qualitativo e quantitativo dos resíduos gerados em todos os laboratórios da FT, buscar ações de minimização de geração, a divulgação do programa de gestão à comunidade acadêmica usuária dos laboratórios e a avaliação de possíveis alternativas de tratamento de resíduos. O levantamento periódico dos resíduos permitiu traçar o perfil de geração dos laboratórios da FT, fundamental para a implantação do plano de gerenciamento. A primeira transferência de resíduos ao abrigo externo e o oferecimento do curso de capacitação resultaram na redução da quantidade de resíduos gerados. No laboratório de cromatografia da FT tem sido realizado há alguns anos o monitoramento de herbicidas triazínicos em amostras ambientais, o que levou a geração desses resíduos orgânicos perigosos. Perante essa condição, foi avaliada uma alternativa de tratamento avançado, via reação de oxidação catalisada por metaloporfirinas, para a degradação dos resíduos de herbicidas triazínicos. As reações de oxidação dos herbicidas triazínicos e os subprodutos gerados foram monitorados por espectrofotometria UV-Vis e cromatografia gasosa. Os rendimentos das reações de oxidação das triazinas com H2O2 e catalisadas pelas metaloporfirinas de ferro (Fe(FTTPCl)) e rutênio (Ru(OCTTPP), variaram de acordo com as condições de reações para a simazina de 9% a 74% e para a atrazina de 12% a 67%, utilizando a Ru(OCTTPP), sendo que para a Fe(FTTPCl) foram de 1,7% a 66% para a simazina, enquanto que para a atrazina foram de aproximadamente 20% nas melhores condições / Abstract: The chemical waste generated in laboratories of universities are complex due to the great diversity of processes of generation and compounds that comprise them. Thus, there is need for a management plan to prevent the waste of diverse composition are inadequately disposed in the environment. In this context are in implementing the Chemical Waste Management Program of Teaching and Research Laboratories of the Faculty of Technology - FT / UNICAMP. With purpose of contribute to the implementation of the FT's Management Program, this project aimed to carry out management actions as the qualitative and quantitative diagnostic of the waste generated in the whole laboratories from FT, to look for actions to minimize the waste generation, dissemination of management program for the academic community users of the laboratory and the evaluation of possible alternatives for waste treatment. The periodic survey of waste allowed tracing the profile generation FT Laboratories, has been crucial for the implementation of the management plan. The first waste transference for the external shelter and the offering of the training course resulted in reducing the amount of waste generated. In the chromatography laboratory of FT was performed for several years monitoring triazine herbicides in environmental samples, with the generation of hazardous organic wastes. In this connection, the another aim of the present work has focused in a advanced treatment alternative by oxidation reaction catalyzed by metalloporphyrins for the degradation of triazine herbicides residues. The oxidation reactions of the triazines herbicides wtih H2O2 and catalized by iron (Fe(FTTPCl) and ruthenium (Ru(OCTTPP)) metalloporphyrins were obtained with variation according to the reactions conditions, from 9% to 74% for simazine and from 12% to 67% for atrazine, using Ru(OCTTPP), while for Fe(FTTPCl) the yields were from 1.7% to 66% for simazine and ca. 20% for atrazine at the best conditions / Mestrado / Tecnologia e Inovação / Mestre em Tecnologia