Kyoto University (京都大学) / 0048 / 新制・論文博士 / 博士(工学) / 乙第12199号 / 論工博第3988号 / 新制||工||1438(附属図書館) / 26271 / UT51-2008-C969 / (主査)教授 堀井 文敬, 教授 渡辺 宏, 教授 金谷 利治 / 学位規則第4条第2項該当

Made available in DSpace on 2014-06-11T19:24:40Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-02-17Bitstream added on 2014-06-13T20:52:19Z : No. of bitstreams: 1 horimoto_lk_me_botfca.pdf: 643530 bytes, checksum: a89cce04a174ddfc6169b6fc1e10b14b (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / Apesar dos amidos serem quimicamente iguais, a organização e funcionalidade desses polímeros dependem das propriedades físico-químicas de cada fonte botânica. Esses amidos podem sofrer diferentes modificações com a finalidade de aperfeiçoar certas características para aplicações industriais específicas. Dentre os amidos modificados, os catiônicos são largamente utilizados na fabricação de papel/papelão a fim de aumentar sua resistência física e mecânica. Neste trabalho, amidos de mandioca, batata doce e mandioquinha salsa foram cationizados com o reagente 3-cloro-2-hidroxipropil-trimetilamônio que em meio alcalino reage com o amido tornando-o carregado positivamente.As amostras foram submetidas a diferentes tempos de reação (0,5 a 24 horas) e relação molar de hidróxido de sódio/monômero. Os melhores parâmetros encontrados para as amostras foram de 6 horas de reação e relação molar de 2,0 NaOH/monômero, que resultaram em maiores DS (grau de substituição) e rendimento percentual, determinados a partir do teor de nitrogênio presente em cada amostra. Em seguida os amidos catiônicos com os melhores parâmetros foram submetidos a diferentes tratamentos após a derivatização: etanol a 25%, etanol a 50% e água a temperatura de 35°C, para avaliar a interferência dos sais residuários no grau de substituição das amostras derivatizadas. A seguir essas amostras de amidos catiônicos de mandioca, batata doce e mandioquinha salsa foram aplicadas em folhas de papel, onde testes físicos-mecânicos como resistências ao rasgo, arrebentamento, tração, permeância ao ar entre outros foram realizados com a finalidade de verificar a influência da adição de diferentes tipos de amido. / In spite of starches are chemically the same, the organization of biopolymers and the functionality of the starches depend on physical and chemical properties of each botanical source, which can undergo modifications with the purpose of improving certain characteristics for specific industrial applications. Among the modified starches, the cationic are widely used in the papermaking process in order to increase their physical and mechanical resistances. In this study, cassava, sweet potato and Peruvian carrot starches were cationized with 3-chloro-2-hydroxypropyltrimethylammonium choride reagent, that in a high pH reacts with starch become it positively loaded. The samples were submitted to different reaction time (0.5 to 24 hours) and the NaOH/monomer mole ratio. The best parameters found for the samples were of 6 hours of reaction time and 2.0 NaOH/monomer mole ratio, which resulted in larger degree of substitution (DS) and reaction efficiency (RE), determined by the 3 content of nitrogen present in each sample. Then the cationic starches with the best parameters were submitted to different treatments after derivatization: ethanol at 25%, ethanol at 50% and water at the temperature of 35°C, in order to evaluate the interference of the residual salts in the degree of substitution of the derivatized samples. In the sequence, these samples of cationic cassava, sweet potato and Peruvian carrot starches were applied in sheets of paper, where physical and mechanical tests such as air resistance, bursting strength, tensile strength, internal tearing resistance, among others, were performed with the purpose of verifying the influence of the addition of different types of starch.

Orientador: Eloi da Silva Feitosa / Banca: Pietro Ciancaglini / Banca: Rosangela Itri / Banca: João Ruggiero Neto / Banca: Vera Aparecida de Oliveira Tiera / Resumo: Estudos de calorimetria diferencial de varredura (DSC) e fluorescência de estado estacionário da sonda Vermelho do Nilo indicam a formação de vesículas de DODAX (X = Cl- ou Br-) em concentrações de surfactantes tão baixas quanto 10 µM. Estas vesículas foram denominadas microvesículas (µV), cuja Tm diminui monotonicamente com a concentração de DODAX até valores de Tm das vesículas tradicionais preparadas em 1.0 mM do surfactante. O efeito do contra-íon (Br- e Cl-) no comportamento termotrópico de fase das vesículas mistas de DODAB-DODAC foi investigado por DSC, condutimetria e espalhamento dinâmico de luz (DLS). Observou-se que a Tm aumenta sigmoidalmente de 45.8 a 48.9 oC com a fração molar de DODAC (xDODAC), com um ponto de inflexão no ponto eqüimolar. A condutividade e o diâmetro hidrodinâmico das vesículas variam muito pouco com xDODAB, indicando que a densidade superficial de carga das vesículas de DODAX é semelhante entre si, e o efeito do contra íon na Tm de DODAX se deve a interações específicas desses contra-íons na interface das vesículas. Medidas de DSC, fluorescência e turbidez de misturas de DODAB-DDAB indicam que as vesículas de DODAB têm maior afinidade por DDAB do que o oposto, resultando na formação de duas populações de vesículas mistas de DDAB-DODAB, com propriedades distintas. Além disso, medidas de fluorescência mostraram que a presença de pequena quantia de DODAB incorporado nas vesículas de DDAB causa um efeito significante na emissão da sonda devido ao aumento do tamanho das vesículas, sugerido por medidas de turbidez. O estudo dos sistemas DODAB/CnTAB/água na concentração total de surfactante igual a 1,0 e 5,0 mM, variando a concentração de CnTAB, e também mantendo a concentração de DODAB fixa em 1,0 mM, revelou uma forte dependência do comprimento da cadeia de hidrocarbonetos... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Differential scanning calorimetry (DSC) and fluorescence of the probe Nile Red studies reveal the formation of DODAX vesicles (X = Br- and Cl-) at surfactant concentrations as low as 10 µM. These vesicles were referred to as microvesicles (mV), whose Tm decreases monotonically with increasing DODAX concentration to the value for the ordinary vesicles at 1 mM. The effect of counterion (Br- and Cl-) on the thermotropic phase behavior of mixed DODAB-DODAC vesicles were investigated by differential scanning calorimetry (DSC), conductimetry and dynamic light scattering (DLS). Tm increases sigmoidally from 45.8 to 48.9 oC with DODAC molar fraction (xDODAC), with an inflection point at the equimolarity. The conductivity and the apparent hydrodynamic diameter vary little with xDODAB, indicating that the surface charge density is similar for DODAX, evidencing that the effect of counterion on Tm is due to the counterion specific interactions. DSC, fluorescence and turbidity measurements indicate a higher affinity of DDAB for DODAB vesicles than the reverse, resulting in two populations of mixed DDAB-DODAB vesicles with different properties. Besides, fluorescence measurements show that the presence of a small amount of DODAB in DDAB vesicles causes a pronounced effect on the Nile Red emission, due to the increase in vesicle size, as suggested from turbidity results. The study of DODAB/CnTAB/água systems at 1.0 and 5.0 total surfactant concentration, and varying CnTAB concentrations with constant 1.0 mM DODAB revealed a strong dependence of the chain length n and relative concentration of the surfactante in the properties of mixed DODAB-CnTAB vesicles. This study allowed analyzing the thermotropic phase behavior containing different amount of DODAB, and the mechanism of vesicle-micelle transition with increasing CnTAB concentration, below and above CMC... (Complete abstract click electronic access below) / Doutor

La mucoviscidose est une maladie génétique grave et évolutive dont les atteintes pulmonaires sont, aujourd’hui, les causes principales de décès des patients. Du fait de l’absence ou du dysfonctionnement du canal chlore CFTR, les patients atteints de mucoviscidose présentent un mucus hypervisqueux notamment au niveau des voies respiratoires. Ce mucus est un environnement favorable à la colonisation par des bactéries opportunistes telles que le Staphylococcus aureus ou le Pseudomonas aeruginosa. La chronicité des infections couplées avec une inflammation importante conduisent à la dégradation progressive des fonctions respiratoires. Actuellement, hormis la greffe coeur/poumon, aucun traitement curatif n’est encore accessible pour l’ensemble des patients. L’approche par thérapie génique apparait être une bonne stratégie pour tenter de guérir tous les patients indépendamment du type de mutations dont ils sont porteurs. Il s’agit d’apporter une copie saine du gène CFTR à l’intérieur des cellules afin que celles-ci expriment une protéine fonctionnelle. Pour ce faire, de nombreuses barrières sont à franchir. Parmi elles, la présence de bactéries dans l’environnement cellulaire est un frein s’opposant au transfert de gènes notamment par vecteurs. Il semble pertinent de développer une formulation multifonctionnelle permettant d’une part d’éliminer les bactéries en surface et d’autre part, de transfecter les cellules cibles. Cette formulation doit rester efficace après qu’elle ait été aérosolisée. Au cours de ce travail, plusieurs formulations, incorporant des lipides cationiques et des composés argent, ont été mises au point. / Cystic fibrosis is a genetic disease with lung damages as the current main causes of death. Due to the absence or dysfunction of the CFTR chloride channel, CF patients have hyper-viscous mucus, particularly in the respiratory tract. This mucus is an environment favorable to infection development by opportunistic bacteria such as Staphylococcus aureus or Pseudomonas aeruginosa. The chronicity of infections coupled with significant inflammation leads to the progressive degradation of respiratory functions. Currently, apart from the heart-lung transplantation, no cure is still available for all patients.The approach by gene therapy appears to be a good strategy to cure all patients regardless of the type of mutations they have. It is a matter of bringing a healthy copy of the CFTR gene into the cells so that they express a functional protein. To do this, many barriers must be overcome. Among them, the presence of bacteria in the cellular environment is a brake against the transfer of genes in particular by vectors. It seems pertinent to develop a multifunctional formulation that on the one hand eliminates surface bacteria and on the other hand transfect the target cells. This formulation must remain effective after it has been aerosolized. During this work, several formulations, incorporating cationic lipids and silver compounds, have been developed.

A Anfotericina B (AB) é um antibiótico antifúngico natural, do grupo dos polienos, produzido por cultura de bactérias Streptomyces nodosus. A AB foi isolada pela primeira vez em 1953, e desde então tem sido utilizada extensivamente no tratamento clínico de infecções sistêmicas. Como a AB é altamente insolúvel em meio aquoso, a formulação de escolha tem sido dispersões aquosas de micelas mistas de AB e desoxicolato de sódio (Fungizon). Entretanto, a alta toxicidade deste fármaco tem estimulado a proposição de várias outras formulações. O presente trabalho estuda uma dessas formulações alternativas propostas: agregados de AB e Brometo de dioctadecildimetilamônio (DODAB). O objetivo principal deste trabalho foi tentar avaliar, numa visão estrutural, as propriedades e peculiaridades envolvidas na interação da AB com as dispersões de DODAB. Neste trabalho, centrou-se no estudo de dispersões de DODAB, sonicadas (DODABS) e não sonicadas (DODABNS), onde o antibiótico estivesse, principalmente, na forma monomérica, tendo em vista a proposta baixa toxicidade da AB enquanto monômero. Para avaliar estes sistemas utilizaram-se as técnicas de absorção óptica, calorimetria diferencial de varredura (DSC) e a Ressonância Paramagnética Eletrônica (RPE) de marcadores de spin incorporados nos agregados lipídicos. Mostrou-se que a AB monomérica incorpora-se tanto em vesículas de DODABNS, como nos pequenos agregados de DODABS, sendo maior sua incorporação nestes últimos. Foi possível mostrar que até a fração molar (AB/DODAB) de 1,2 mol% a AB está totalmente monomérica, incorporada em agregados de DODABS, mas somente parcialmente em vesículas de DODABNS. Nas bicamadas de DODABNS, a preferência da AB monomérica é pela fase gel, 40 % incorporada, comparada com 23 % na fase fluida. As várias técnicas indicam que a AB encontra-se na superfície da bicamada, com seu cromóforo hidrofóbico enxergando um meio de polarizabilidade maior do que a da água, tanto em DODABS como em DODABNS. Marcadores de spin mostram a coexistência de domínios lipídicos em fases diferentes, gel e fluida, a baixas temperaturas, em DODABS. Curiosamente, indicam que a AB monomérica interage, preferencialmente, com os domínios mais fluidos, em desacordo com a observada maior afinidade da AB pela fase gel de bicamadas lipídicas de DODABNS. O estudo termo-estrutural de dispersões de DODABNS e DODABS aqui apresentado, na presença e ausência de AB, pode ser relevante na proposta de novas formulações farmacológicas. / Amphotericin B (AB) is a natural antibiotic, produced by Streptomyces nodosus, with a very potent antifungal activity. It is a polyene macrolide molecule, isolated in 1953. Since then, it has been extensively used in the treatment of systemic mycotic infections. Considering AB very low solubility in aqueous medium, it has been largely used as an aqueous dispersion of sodium deoxycholate-AB mixed micelles (Fungizon). However, the high toxicity of this preparation has led to the proposition of different other formulations. The present work focuses on one of the proposed preparations, namely aggregates formed by AB and the cationic lipid dioctadecyldimethylammonium (DODAB). Considering the proposed low toxicity of monomeric AB, the present work studies DODAB dispersions, sonicated (DODABS) and non-sonicated (DODABNS), where AB is mostly monomeric. To the structural analysis, optical absorption, differential scanning calorimetry (DSC) and electron spin resonance of spin labels incorporated in the aggregates were used. It was found that AB as a monomer incorporates in aggregates present in both dispersions, DODABS and DODABNS, but the incorporation of monomeric AB in the small fragments present in DODABS is much larger. It was shown that AB incorporates in DODABS aggregates, as a monomer, up to AB/DODAB concentration of 1.2 mol%. At this concentration, only 40 % and 23 % of AB molecules are in the monomeric state in the gel and fluid phases of DODABNS bilayers, respectively. Hence, the gel phase of DODABNS bilayers favors the monomerization of AB, as compared to the bilayer fluid phase. All the applied techniques point to a superficial interaction of monomeric AB with DODAB aggregates, with the hydrophobic polyene chromophor positioned relatively inside the bilayer, in a region of polarizability higher than that of water, in both dispersions, DODABS and DODABNS. Spin labels indicate the coexistence of gel and fluid domains in DODABS aggregates, at low temperatures, supporting the proposed hypothesis of the presence of bilayer fragments in the dispersion. Contrarily to the higher detected affinity of monomeric AB for the gel phase, as compared to the fluid phase of DADABNS bilayers, spin labels indicate that monomeric AB is mostly adsorbed at the fluid domain of the fragments, possibly corresponding to the periphery of the fragments. The thermal-structural study presented here of DODABNS and DODABS, in the presence and absence of AB, can be relevant in the design of new pharmaceutical formulations.

Made available in DSpace on 2014-08-20T13:32:59Z (GMT). No. of bitstreams: 1 tese_vinicius_farias_campos.pdf: 556217 bytes, checksum: 4c9dc7811c567f171aaebfafce2d2254 (MD5) Previous issue date: 2011-07-29 / Nanobiotechnology has provided new scientific and technological knowledge in distinct areas making it a priority area of research in developed and developing countries. The sperm-mediated gene transfer (SMGT) technique may become more simple, efficient and cost-effective technique for the generation of transgenic animals. The development of nanocomposites able to carry foreign DNA into the nucleus of cells with greater efficiency allows techniques such as SMGT be improved. The NanoSMGT is a technique used to generate transgenic animals in which nanotechnology is used to enhance the ability of sperm to capture exogenous DNA. The objective of this study was to determine whether cationic nanopolymer or halloysite clay nanotubes are able to transfect the exogenous DNA to unsorted and sex-sorted bovine sperm then evaluate whether these sperm are able to transmit transgene to in vitro fertilized bovine embryos. Using real-time PCR, we found that the cationic nanopolymer is capable of introducing exogenous DNA into unsorted and sex-sorted bovine sperm without negative effects to sperm motility and viability. Was also demonstrated for the first time that cationic nanopolymer or halloysite clay nanotubes are able to increase both the sperm DNA transfection of as the transmission of the transgene to bovine embryos produced in vitro. These results demonstrate that NanoSMGT can be a viable technique for producing transgenic bovine embryos. / A nanobiotecnologia tem proporcionado novos avanços científicos e tecnológicos em diversas áreas do conhecimento tornando-se assim área de pesquisa prioritária em países desenvolvidos e em desenvolvimento. A transferência gênica mediada por espermatozóides (SMGT) poderá se tornar a técnica mais simples, eficiente e com melhor custo-benefício para a geração de animais transgênicos. O desenvolvimento de nanocompósitos capazes de carrear o DNA exógeno para o interior de células com maior eficiência permite que técnicas como a SMGT sejam aperfeiçoadas. A NanoSMGT é uma técnica utilizada para a geração de animais transgênicos onde a nanotecnologia é utilizada para incrementar a habilidade dos espermatozóides em capurar o DNA exógeno. O objetivo do presente trabalho foi de verificar se nanopolímero catiônico ou nanotubos de haloisita são capazes de transfectar o DNA exógeno para o interior de espermatozóides bovinos sexados e não sexados e em seguida verificar se estes espermatozóides transfectados são capazes de gerar embriões bovinos transgênicos. Utilizando PCR em tempo real, verificou-se que o nanopolímero catiônico é capaz de introduzir o DNA exógeno em espermatozóides bovinos sexados e não sexados sem danos para a motilidade e viabilidade espermática. Também foi demonstrado pela primeira vez que o nanopolímero catiônico ou os nanotubos de haloisita são capazes de incrementar tanto a transfecção de DNA em espermatozóides como a transmissão do transgene para embriões bovinos produzidos in vitro. Estes resultados demonstram que a NanoSMGT pode ser uma técnica viável para a produção de embriões bovinos transgênicos.

The thesis entitled “Evolution of New Lipids and Molecular Gelators: Syntheses, Aggregation Properties and Applications” elucidates the design, synthesis, aggregation properties and application of new lipids based on α-tocopheryl backbone and also with triazacyclononane (TACN) moiety. This thesis also elucidates the synthesis and aggregation properties of molecular gelators based on pyrene-pentapeptide and naphthalene diimide (NDI) moiety. The work has been divided into five chapters. Chapter 1: Introduction: Self-assembled Molecular Aggregates and their Potential Applications This chapter describes the importance of different self-assemble mainly lipids and molecular gelator. Lipids mediated gene delivery, drug delivery and metal ion induced interaction are discussed. For liposomal gene delivery here we mainly describe example of cationic gemini lipids. This chapter also gives a comprehensive account of the research towards the development of novel liposomal drug delivery containing tocopheryl backbone. It also includes the utilization of liposome which could coordinate with metal ions and their interaction with different biological analyte. Here we also discuss a wide range of molecular gelator mainly based on NDI and amino acid or peptide. Chapter 2A: Physicochemical Characterization of Bilayer Membranes Derived from (±) α-Tocopherol Based Gemini Lipids and their Interaction with plasmid-DNA and Phosphatidylcholine Bilayers In this sub-chapter we discuss the membrane formation and aggregation properties of a series of (±) α-tocopherol based cationic gemini lipids (Figure 1) varying polymethylene spacer length (TnS; n = 3, 4, 5, 6, 8 and 12) are studied extensively while comparing with corresponding properties of monomeric counterpart (TM). Liposomal suspensions of all cationic lipids are characterized by atomic force microscopy (AFM), transmission electron microscopy (TEM), dynamic light scattering (DLS), zeta potential measurements and small angle x-ray diffraction studies. Aggregation properties of the gemini lipids are highly dependent on the spacer length and were significantly distinct from that of monomeric lipid (TM). Figure 1. Molecular structures of (±) α-tocopherol based cationic monomeric and six gemini lipids that differ in polymethylene spacer length. Stable monolayer formation at air water interface formation of each amphiphile is studied by Langmuir film balance technique. Interaction of liposome with plasmid DNA is studied by ethidium bromide (EB) intercalation assay. Micellar sodium dodecyl sulphate (SDS) mediated release of the plasmid DNA from various pre-formed lipoplex is also studied. Structural transformation of pDNA upon complexation with liposome is characterized by circular dichroism (CD) spectroscopy. Interaction of all tocopheryl lipids with a model phospholipid, L-α-dipalmitoyl phosphatidylcholine (DPPC) derived vesicles is thoroughly examined by differential scanning calorimetry (DSC) and DPH fluorescence anisotropy measurements. Succinctly, we perform a detailed physicochemical characterization on cationic monomeric and gemini lipids bearing tocopherol as their hydrophobic backbone. Chapter 2B: Physicochemical Characterization of Bilayer Membranes Derived from (±) α-Tocopherol Based Gemini Lipids Containing Hydroxyethyl Functionality in the Headgroups and their Interaction with plasmid-DNA and Phosphatidylcholine Bilayers This sub-chapter describes the synthesis and aggregation properties of series of tocopheryl-based monomeric and gemini cationic lipids with hydroxyethyl functionality (Figure 2) in the headgroup region. Gemini lipids of this given series differ in their polymethylene spacer -(CH2)n- chain lengths between cationic headgroups. All monomeric and gemini lipids are found to generate stable suspensions in aqueous media. Average hydrodynamic diameter and surface charge of liposome are characterized by DLS and zeta potential measurements. Atomic force microscopy and transmission electron microscopic studies show that all lipids form vesicular Figure 2. Molecular structures of (±) α-tocopherol based cationic monomeric and five new lipids with hydroxyethyl functionality in the headgroups that differ in polymethylene spacer length aggregates in aqueous media. XRD studies with the cast films of lipids reveal interdigitated bilayer arrangement of liposome. pDNA binding and release studies show that the interactions between gemini lipids and DNA depend upon the nature of head group as well as the length of the spacer between cationic head groups. Circular Dichroism (CD) spectra of lipoplex are measured to characterize structural transformation of pDNA upon complexation with liposome. DPH anisotropy and DSC studies of the DPPC-cationic lipid co-aggregates show that ~20 mol-% of of the tocopheryl gemini lipids is enough to abolish phase transition of DPPC membranes whereas more than 20 mol-% is required in case of their monomeric counterparts. Furthermore thermotropic properties of co-aggregates depend upon the length of the spacer of gemini lipid included in the mixture. Chapter 2C: Transfection Efficacies of α-Tocopherol Based Cationic Gemini Lipids with Hydroxyethyl Containing Headgroups. In this sub-chapter, we demonstrate transfection efficiency of five α-tocopheryl gemini lipid with hydroxyethyl containing headgroups (Figure 3). Co-liposomal formulations with helper lipid 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine (DOPE) form highly stable formulations in water. Co-liposomal formulations with high molar ratio of DOPE (1.5:1 and 2:1) show higher transfection efficiency than liposome with low DOPE content liposome. Co-liposome of gemini lipids with longer spacer (n = 8 and 12) have higher level of luciferase expression in HepG2 cell line. In A549 and MCF-7 cell lines also co-liposomes of TH8S (2:1) are proved to be better than other co-liposome. N/P ratios of highest transfection are 1-1.5. These formulations are more potent than L2K in all three cancer cell line. The comparison with gemini lipid (T8T) without Figure 3. Molecular structures of (±) α-tocopherol based cationic gemini lipids that differ in polymethylene spacer length and helper lipid DOPE. hydroxylethyl group also proves the importance of hydroxyethyl functionalities. High serum stability of DOPE-gemini lipid formulation is attributed to tocopherol backbone and also hydroxyethyl functionalities. Circular dichroism data also show that lipoplex of DOPE-TH8S (2:1) have different conformation than the other. Relatively moderate binding efficiency and easy release of pDNA is also observed with DOPE-TH8S (2:1) in the EB-displacement assay which could be plausible reason for high transfection efficiency. Chapter 2D: Reduction Responsive Nanoliposomes of α-Tocopheryl-Lipoic Acid Conjugate for Efficacious Drug Delivery to Sensitive and Resistant Cancer Cells In this sub-chapter, we present lipid conjugates derived from biologically relevant molecules, i.e., tocopherol and lipoic acid (Figure 4). These conjugates (TL1 and TL2) are able to form stable nanoliposomes (~100 nm) that respond to the reducing environment of cells as shown by the treatments of 1,4-Dithiothreitol (DTT) and Glutathione (GSH). Figure 4. Molecular structures of tocopheryl-lipoic acid conjugates, TL1 and TL2 Nanoliposomes could efficiently load the drug (DOX) molecules and release them in response to the stimulus. Nanoliposomes are stable enough in the presence of serum and could deliver DOX inside drug sensitive and drug resistant cells in an efficient manner that is even better than the drug alone treatments as shown by means of flow cytometry and confocal microscopy analysis. DOX loaded nanoliposomal formulations show relatively less cell viability counts than those drug alone treatments. Chapter 3A: Interaction of Nickel (II) and mida ole it Triazacyclononane Modified Chelator Amphiphiles: A Potential Substrate for Immobilization of His-tag Protein on Hydrophilic Surface This sub-chapter describes two chelator amphiphiles based on 1, 4, 7-traiazaclonone (TACN) (Figure 5). These compounds could bind efficiently Ni2+ ion. Self-assemble of these amphiphiles form vesicular aggregates. Their packing properties of these amphiphiles are influence by Ni2+ and imidazole. Also influence of Ni2+ and imidazole in Langmuir monolayer isotherm of these amphiphiles at air-water interface are also studied. Figure 5. Molecular structures of TACNA chelator amphiphiles. These studies show the newly synthesized amphiphiles could immobilize histidine tagged protein on both bilayer and monolayer surface. One of these compounds with Ni2+ (C16TACNA-Ni2+) is used to transfer a His-tagged protein nucleolin on hydrophilicobic glass surface by Langmuir-Blodgett transfer technique. So, these compounds with Ni2+ could be very useful to attach different His-tagged protein or polypeptide of interest on the bilayer (liposome) or monolayer surface. Chapter 3B: Supramolecular Hosts for Enhancing the Selectivity of TACN Based Probes towards Copper (II): Differential Output Signals for Cysteine and Histidine In this sub-chapter, we have developed a new amphipathic probe compound 1 having TACN as the binding site and dansyl as signaling moiety (Figure 6). As TACN is known for its’ unspecific interaction with multiple ions, the probe shows response with most of the transition metal ions. However, incorporation into different supramolecular hosts (like micelle and vesicles) drastically improves the selectivity of compound 1 towards Cu2+ (diminution of bright green fluorescence) in water. Then we Figure 6. Molecular structures of dansylated TACN chelator amphiphiles. have also employed the Cu2+ complex of compound 1 for selective estimation of amino acids. Addition of cysteine regains the green emission of compound while histidine exhibits blue intense emission upon formation of ternary conjugate. Chapter 4: Transforming a β-Sheet Pyrenylated-VPGKG Sequence into pH Tolerent, Thixotropic Hydrogel by Arene-Perfluoroarene Interactions and Visualized Sensing of Calcium (II) Ion In this chapter we discuss self-assembly studies of a novel thermoresponsive, lipidated, pyrene-appended peptide, PyP (Figure 7). Size of the vesicular aggregates of the β-sheet forming peptide, PyP, strongly depends on the temperature of the solution in water. Further pyrene-octafluoronaphthalene (OFN) pair has been used as supramolecular synthon to induce hydrogelation of PyP in presence of equimolar amount of OFN via complementary quadrupole-quadrupole interactions. The gel shows excellent pH tolerant as well as thixotropic behavior. Detailed studies suggested the lamellar packing of the gelator in a right-handed helical fashion yielded vesicular aggregates. The sticky vesicles form gel via inter- Figure 7. Molecular structure of the Pyrenylated-VPGKG peptide (PyP) and octafluoronapthalene (OFN). Ca2+ ion reinforces the mechanical strength and also reduces the critical gelator concentration of the native gel through coordination with the free -COO- group of the gelator. Therefore, this present system could be used as a visualized sensor of Ca2+ ion. Chapter 5: First Report of Naphthalenediimide Based Metallo(organo)gel In this chapter, we have demonstrated synthesis of a novel asymmetric bolaamphiphilic (Figure 8). NDI derivative is capable of self assemble into stable gel in EtOH. Detailed studies reveal the gelator molecule of 1 adopt a parallel alignment in the lamellae during self-aggregation as nanoscopic spherical assemblies. In addition, dried gel of 1 shows nematic liquid crystalline phase. Further, we synthesize a novel metal-ligand discrete complex 2 in a nearly quantitative yield by reacting equimolar amount of 1 and PdCl2(PhCN)2. Figure 8. NDI derivative, 1, and its discrete metal complex 2. Complex 2 has been found to yield stable gel in dichloromethane (DCM) or chloroform (CHCl3) through the formation of high aspect ratio fibers. ROESY NMR experiment of Complex 2 has been found to yield stable gel in dichloromethane (DCM) or chloroform (CHCl3) through the formation of high aspect ratio fibers. ROESY NMR experiment of

Ce travail est une contribution à la compréhension de la structure à courte et moyenne distance des verres à base de TeO₂ via de nouveaux verres au sein des systèmes TeO₂-TiO₂-WO₃ (TTxWy) et TeO₂-NbO₂ ̩₅-WO₃ (TNxWy). De pertinentes corrélations sont révélées entre leurs propriétés structurales (en utilisant la spectroscopie Raman) et optiques. Globalement, l’ajout de TiO₂, WO₃ ou NbO₂ ̩₅ n’engendre aucune évolution structurale brutale. L’ajout de TiO2 induit une séparation de phases entre les régions amorphes riches en TiO2 et le réseau riche en TeO2. Cette interprétation est en accord avec le comportement structural prédit par la théorie de Dietzel sur la force de champ cationique. L’ajout de WO3 entraîne l’apparition (i) d’octaèdres WO₆ uniformément dispersés à travers le réseau des ponts Te–O–Te (pour de faibles teneurs en WO₃) et (ii) de régions riches en WO3 (pour des teneurs plus importantes en WO₃). L’ajout de NbO₂ ̩₅ engendre (i) une faible dépolymérisation structurale du réseau Te–O–Te et (ii) l’apparition des régions riches en NbO₂ ̩₅. Les verres étudiés sont dotés de forts indices de réfraction linéaires (2.19 dans TTxWy et 2.13 dans TNxWy en moyenne) et de remarquables susceptibilités non linéaires χ(3) (7.03 *10-13 esu dans TTxWy et 5.48 *10-13 esu dans TNxWy en moyenne, i.e., ~47 et ~37 fois plus élevées que la valeur de χ(3) du verre SiO₂). / In this work, we present a contribution to the understanding of the short- to medium-range structure of TeO₂-based glasses via new glasses within the TeO₂-TiO₂-WO₃ (TTxWy) and TeO₂-NbO₂ ̩₅-WO₃ (TNxWy) systems. Consistent correlations are revealed between their structural (using Raman spectroscopy) and optical properties. Globally, no striking structural evolutions take place upon adding TiO₂, WO₃ or NbO₂ ̩₅. Adding TiO2 results in a phase-separation between amorphous TiO₂-rich regions and TeO2-rich network, in harmony with the predicted structural behavior on the basis of Dietzel’s cationic field strength theory. Adding WO₃ leads to (i) uniformly dispersed WO₆ octahedra throughout the Te–O–Te network (at low WO₃ contents) and (ii) amorphous WO₃-rich regions (at higher WO₃ contents). Adding NbO₂ ̩₅ engenders (i) a weak structural depolymerization of the Te–O–Te network and (ii) occurrence of NbO₂ ̩₅-rich regions. The investigated glasses exhibit high linear refractive indices (averages of 2.19 in TTxWy and 2.13 in TNxWy) and remarkable nonlinear susceptibilities χ(3) (averages of 7.03 *10-13 esu in TTxWy and 5.48 *10-13 esu in TNxWy, i.e., ~47 and ~37 times higher than χ(3) of SiO₂ glass).

This study investigates electrochemical oxidation of m-cresol on boron-doped diamond electrode using direct current voltammetry (DCV), differential pulse voltametry (DPV) and cyclic voltammetry (CV). In aqueous media in pH range 2.0 - 12.0 m-cresol provides one oxidation peak. The electrode reaction is diffusion-controled. Because of electrode passivation two types of pretreatment were applied for reactivation of electrode surface., i.e. alumina polishing and anodic activation using potential of +2400 mV. Peak heights and potentials are strongly dipending on the type of pretreatment for DCV and DPV - the difference in peak potentials can reach 430 mV. Using optimal conditions for alumina polishing in 0.01 μmol·L-1 NaOH the linear dynamic range is 1.0 - 75 μmol·L-1 for DCV and 0.75 - 75 μmol·L-1 for DPV. And for anodic activation in BR buffer pH 2.0 the linear dynamic range is 0.75 - 75 μmol·L-1 for DCV and DPV. The influence of boron-doping level was investigated using a semiconductive and mettalic-type BDD film. For the latter the sensitivity in DP voltammetry is two times higer and for both types the linear dynamic range is ca 1 - 25 μmol·L-1 . The voltammetric response of m-cresol was further investigated in the presence of cationic surfactants. In the presence of CTAB and CPB the peak current...

Les travaux réalisés au cours de cette thèse sont centrés sur la synthèse et la réactivité de ligands phosphorés à caractère faiblement s-donneur et fortement p-accepteur. Il s'agit de ligands phosphines présentant une charge cationique en position a de l'atome de phosphore. Cette charge positive est amenée alternativement par un fragment amidinium ou bien cyclopropénium, conduisant respectivement aux amidinio- et cyclopropéniophosphines. Ces travaux sont présentés en trois chapitres. Dans le premier chapitre, après un partie bibliographique, nous avons décrit la synthèse de di-imidazolo- et di-imidazoliophosphines diversement P-substituées par des groupements aryle, alkyle et di(alkyl)amino. L'étude de la réactivité de ces ligands vis-à-vis d'acides de Lewis métalliques ou non a permis de démontrer que la nature du substituant porté par l'atome de phosphore influençait de façon critique les propriétés de coordination. Divers complexes métalliques et oxydes de phosphines ont été ainsi obtenus et entièrement caractérisés. Dans le deuxième chapitre, nous nous sommes intéressés à la préparation de phosphines a-cationiques chirales. Deux cas distincts ont été ainsi considérés : des phosphines cationiques à chiralité électrostatique dans lesquelles l'effet électrostatique prime sur l'effet stérique et des phosphines cationiques à chiralité stérique dans lesquelles l'effet stérique est cette fois-ci prédominant. Il a été démontré qu'en dépit des effets électroniques et stériques présents, ces phosphines étaient capables de se coordiner à un centre métallique. Divers complexes de métaux de transition de ces phosphines P-chirogènes ont été ainsi préparés et entièrement caractérisés. Dans le cas des phosphines à chiralité électrostatique, une version énantiopure a été isolée grâce à l'utilisation d'un complexe de palladium(II) orthométallé optiquement actif comme agent de dédoublement. Le troisième chapitre est axé sur le développement de ligands carbonés anioniques fortement donneurs de type imidazolyle et de leurs complexes. Afin de contre-balancer l'extrémité carbonée donneuse, une partie phosphorée acceptrice de type imidazolophosphine a été introduite. En série rhodium(I), deux complexes de ces ligands chélatants hybrides phospho-carbonés ont été ainsi isolés et caractérisés. / The project developed during this PhD thesis aims at the synthesis and reactivity of phosphorus ligands with weak s-donor and strong p-acceptor properties. They correspond to phosphine ligands featuring a cationic charge in a position of the phosphorus atom. The cationic charge can be introduced alternatively through an amidinium or a cyclopropenium moiety affording amidinio- and cyclopropeniophosphines, respectively. In the first chapter, after a bibliographical section, the synthesis of di-imidazolo- and di-imidazoliophosphines with aryl, alkyl and dialkylamino P-substituents is described. The study of the reactivity of these phosphine ligands towards metallic (or not) Lewis acids demonstrates that the nature of the P-substituent influences dramatically the corresponding coordination properties. Various cationic metal complexes and phosphine oxides are obtained and fully characterized. The second chapter of the thesis is focused on the development of chiral a-cationic phosphines. Two different cases are considered: cationic phosphines with electrostatic chirality where steric effects may be neglected and cationic phosphines with predominant steric chirality. In both cases, despite electron-poor character, these phosphines were shown to coordinate various transition metal centers. In the case of phosphines featuring electrostatic chirality, a representative was isolated in an optically pure form through the use of chiral orthometallated palladium(II) complexes as resolving agents. Finally, the third chapter concerns the development of imidazolyl carbon ligands and the corresponding complexes. In order to balance the electron-richness of the anionic imidazolyl donor extremity, an electron-poor phosphorus coordinating end, namely an imidazolophosphine is introduced. In the rhodium(I) series, two chelating complexes of these hybrid 'rich-poor' carbon-phosphorus ligands have been isolated and characterized.