Nanocomposite thin films can find application in photovoltaics, optics, fabrication of sensors, or in biomedicine. This work investigates fabrication and characterization of thin metal-plasma polymer nanocomposite films which have direct application because of their unique optical properties (e.g. SERS - Surface-Enhanced Raman Spectroscopy) or antibacterial effects (biomedicine). We fabricated metal nanoparticles either by magnetron sputtering (island growth) or by means of gas aggregation source of nanoparticles, thereby we got nanoparticles with very different morphologies. We used silver as a material for nanoparticles because of its antibacterial effects. We incorporated these nanoparticles into sputtered Nylon and sputtered PTFE (polytetrafluoroethylene) plasma polymer matrix. These two polymers have very different chemical structure and related different surface energy. First, we compared growth of nanoparticles on substrates of sputtered Nylon and PTFE. Then we compared properties of sandwich nanocomposites polymer-Ag-polymer for both types of nanoparticles and for both matrix materials. We characterized produced thin films especially with respect to their stability in water (antibacterial films), thermal stability (sterilization by heating) and stability on the open air (storage). Finally, the tests...

Due to their unique properties, nanoparticles have been a focus of significant research interest for use in various opto-electronic applications, particularly in the field of solar energy generation. In order to realize a nanoparticle-based solar cell, it is important to be able to create thin films of organised nanoparticles and to be able to control their surface properties. In this work the use of a novel synthesis technique involving reaction at the interface between two immiscible liquids to synthesise thin films of lead sulfide nanoparticles on the order of ~10 nm in diameter is reported. The use of the liquid-liquid interface allows the synthesis of particles without the use of stabilising ligands, with sizes and morphologies determined by the conditions present at the interface. Variations in the precursor used, solvent height, and precursor concentration were explored. Films synthesised at various solvent heights displayed a decrease in particle size with increasing solvent height. This trend was seen to vary depending on the lead-containing precursor used. Changes in the precursor concentration resulted in changes in the morphology of the resulting particles as observed with transmission electron microscopy (TEM). Preferential growth along certain planes was observed for particles synthesised with the highest lead precursor concentration. Experiments with precursors with differing organic chain length displayed an increase in particle size with increasing chain length, as well as an increase in preferential growth observed by X-ray diffraction (XRD). Surface ageing was investigated using X-ray photoelectron spectroscopy (XPS) techniques, which showed that all samples followed a similar oxidation mechanism. Oxidised lead species, attributed to hydrated lead oxide, were determined to be the initial oxidation product, formed within a week of exposure to air. Sulfoxy species were observed to form over a greater length of time, with sulfate being determined to be the final oxidation product. An oxidation mechanism is proposed based on XPS analysis of films exposed to air for up to nine months.

The burgeoning field of nanotechnology motivates comprehensive elucidation of nanoscale materials. This thesis addresses transmission electron microscope characterisation of nanoparticle morphology, concerning specifically the crystal- lographic status of novel intermetallic GaPd2 nanocatalysts and advancement of electron tomographic methods for high-fidelity three-dimensional analysis. Going beyond preceding analyses, high-resolution annular dark-field imaging is used to verify successful nano-sizing of the intermetallic compound GaPd2. It also reveals catalytically significant and crystallographically intriguing deviations from the bulk crystal structure. So-called ‘non-crystallographic’ five-fold twinned nanoparticles are observed, adding a new perspective in the long standing debate over how such morphologies may be achieved. The morphological complexity of the GaPd2 nanocatalysts, and many cognate nanoparticle systems, demands fully three-dimensional analysis. It is illustrated how image processing techniques applied to electron tomography reconstructions can facilitate more facile and objective quantitative analysis (‘nano-metrology’). However, the fidelity of the analysis is limited ultimately by artefacts in the tomographic reconstruction. Compressed sensing, a new sampling theory, asserts that many signals can be recovered from far fewer measurements than traditional theories dictate are necessary. Compressed sensing is applied here to electron tomographic reconstruction, and is shown to yield far higher fidelity reconstructions than conventional algorithms. Reconstruction from extremely limited data, more robust quantitative analysis and novel three-dimensional imaging are demon- strated, including the first three-dimensional imaging of localised surface plasmon resonances. Many aspects of transmission electron microscopy characterisation may be enhanced using a compressed sensing approach.

Studies various nanostructured materials have gained considerable interest within the past several decades. This novel class of materials has opened up a new realm of possibilities, both for the fundamental comprehension of matter, but also for innovative applications. The size-dependent effect observed for these systems often lies in their interaction with the surrounding environment and understanding such interactions is the pivotal point for the investigations undertaken in this thesis. Three families of nanoparticles are analyzed: semiconductor quantum dots, metallic silver nanoparticles and rare-earth oxide nanomaterials. The radical scavenging ability of cerium oxide nanoparticles (CeO2) is quite controversial since they have been labeled as both oxidizing and antioxidant species for biological systems. Here, both aqueous and organic stabilized nanoparticles are examined in straightforward systems containing only one reactive oxygen species to ensure a controlled release. The apparent absence of their direct radical scavenging ability is demonstrated despite the ease at which CeO2 nanoparticles generate stable surface Ce3+ clusters, which is used to explain the redox activity of these nanomaterials. On the contrary, CeO2 nanoparticles are shown to have an indirect scavenging effect in Fenton reactions by annihilating the reactivity of Fe2+ salts. Cadmium selenide quantum dots (CdSe QD) constitute another highly appealing family of nanocolloids in part due to their tunable, size-dependent luminescence across the visible spectrum. The effect of elemental sulfur treatment is investigated to overcome one of the main drawbacks of CdSe QD: low fluorescence quantum yield. Herein, we report a constant and reproducible quantum yield of 15%. The effect of sulfur surface treatment is also assessed following the growth of a silica shell, as well as the response towards a solution quencher (4-amino-TEMPO). The sulfur treated QD is also tested for interaction with pyronin Y, a xanthene dye that offers potential energy and electron transfer applications with the QD. Interaction with the dye molecule is compared to results obtained with untreated quantum dots, as well as CdSe/ZnS core shell examples. In another chapter of this thesis, the catalytic potential of silver nanoparticles is addressed for the grafting of polyhydrosiloxane polymer chains with various alkoxy groups. A simple one-pot synthesis is presented with silver salts and the polymer. the latter serves as a mild reducing agent and a stabilizing ligand, once silver nanoparticles are formed in-situ. We evaluate the conversion of silane into silyl ethers groups with the addition of several alcohols, whether primary, secondary or tertiary, and report the yields of grafting under the mildest conditions: room temperature, under air and atmospheric pressure.

Orientador: Celso Aparecido Bertran / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-22T10:56:23Z (GMT). No. of bitstreams: 1 Campos_DaniellaDiasPalombinode_D.pdf: 44951379 bytes, checksum: 1a18d9ffcb14751022a3de58b577f652 (MD5) Previous issue date: 2012 / Resumo: Sistemas auto-organizados, preparados com surfactantes nonilfenil etoxilados com diferentes tamanhos de cadeia etoxilada, foram utilizados para sintetizar nanopartículas de hidroxiapatita (HAP - Ca5(PO4)3OH), que é o fosfato de cálcio majoritariamente presente nos tecidos mineralizados dos vertebrados. O efeito do tamanho do grupo etoxilado do surfactante foi avaliado tanto na formação dos sistemas auto-organizados quanto nas propriedades das partículas de HAP precipitadas in situ nestes sistemas. Cristais líquidos hexagonal reverso, lamelar, hexagonal e cúbicos foram formados, nesta ordem, a medida que surfactantes com maiores grupos etoxilados foram empregados. Os fosfatos de cálcio sintetizados em todos os sistemas auto-organizados apresentaram-se na forma de nanohastes, de modo que as nanohastes formadas nas fases anisotrópicas (cristais líquidos hexagonais e lamelares) apresentaram diâmetros mais uniformes quando comparadas àquelas sintetizadas nos sistemas auto-organizados isotrópicos. O diâmetro das hastes de HAP comparado com as dimensões dos sistemas auto-organizados sugere que estas se formaram pela aglomeração orientada de partículas ainda menores de HAP, o que foi evidenciado por microscopia eletrônica de varredura (SEM-FEG). Estes resultados, em conjunto com medidas de tempo de relaxação transversal (T2) do hidrogênio das moléculas de água presentes nos sistemas auto-organizados, permitem propor que a limitação do tamanho das nanopartículas de HAP seja conseqüência da limitação da difusão iônica in situ e que a morfologia de hastes é resultante da autoorganização das fases. / Abstract: Self-assembled systems from nonylphenol ethoxylate surfactants were prepared using surfactants with different hydrophilic chain lengths. These systems were used to synthesize hydroxyapatite (HAP - Ca5(PO4)3OH) nanoparticles, the main constituent of vertebrates mineralized tissues. The surfactant hydrophilic length influence was evaluated both on the self-assembled systems formation and on the properties of HAP nanoparticles which were obtained by in situ precipitation in these systems. As the surfactant hydrophilic length increased different liquid crystals were formed in this sequence: reverse hexagonal, lamellar, normal hexagonal and cubic mesophases. HAP nanoparticles synthesized in all selfassembled systems had morphology of rods. Particles precipitated in the anisotropic systems (hexagonal and lamellar liquid crystals) had more uniform diameters compared to particles precipitated in the isotropic systems (cubic liquid crystals). The HAP nanorods diameters were bigger than the repetition distances of the self-assembled systems. This occurrence, evidenced by SEM-FEG micrographs of the HAP nanoparticles, suggests that the nanorods were formed by even smaller HAP particles which were previously confined in the hydrophilic domains of the phases, and after the surfactant removal they were neatly clustered as induced by the self-assembled systems. These results along with the transversal relaxation times measurements (T2) for hydrogen in water molecules belonging self-assembled systems, allow us to propose the following: there is a reduced ionic diffusion within the liquid crystals hydrophilic domains and it is the cause for the size particles limitation and the particles morphology is influenced by the self-assembling of the systems. / Doutorado / Físico-Química / Doutora em Ciências

Les nanoparticules plasmoniquespossèdent des propriétés intéressantes grâce àla résonance de plasmon de surface localisé. Enplus de leur grande efficacité de conversionphotothermique due au plasmon, leconfinement de l’échauffement peut êtremodulé par le type de source lumineuseutilisée (impulsionnelle ou continue). Cespropriétés font des nanoparticulesplasmoniques une solution potentielle pour lathérapie contre le cancer par hyperthermie.Afin de développer une telle applicationbiomédicale, il est nécessaire d'optimiserl'absorption de l'énergie lumineuse et le ciblagedes nanoparticules sur la tumeur considérée.Dans cette thèse, l'influence des électronschauds photo-générés sur l'absorptiond’impulsions laser ultracourtes par lesnanoparticules est d'abord étudiée. Ensuite, untravail effectué avec des chimistes, biologisteset médecins pour l'application desnanoparticules d’or irradiées par impulsionslaser ultracourtes à la thérapie contre le cancerest présenté. Enfin, nous présentons une étudepréliminaire sur la photoluminescence denanoparticules plasmoniques, dont l'origine estencore controversée, en appliquant un modèleprenant en compte la nature non thermale dela distribution d’électrons chauds. / Plasmonic nanoparticles possessinteresting properties thanks to the localizedsurface plasmon resonance. In addition totheir high photothermal conversion efficiency,the heat release confinement can bemodulated by the type of light source used(pulsed or continuous laser). These propertiesmake the plasmonic nanoparticles a potentialsolution for cancer therapy by hyperthermia.In order to develop such a biomedicalapplication, it is necessary to optimize theabsorption of light energy and the targeting ofnanoparticles on the tumor considered.In this thesis, the influence of the photogeneratedhot electrons on the absorption ofultrashort laser pulses by nanoparticles is firststudied. Then, a work carried out withchemists, biologists and physicians for theapplication of gold nanoparticles irradiated byultrashort laser pulses to cancer therapy isdescribed. Finally, we present a preliminarystudy on the photoluminescence of plasmonicnanoparticles, the origin of which is stillcontroversial, by applying a model accountingfor the non-thermal nature of the hot electrondistribution.

京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第22460号 / 工博第4721号 / 新制||工||1737(附属図書館) / 京都大学大学院工学研究科物質エネルギー化学専攻 / (主査)教授 近藤 輝幸, 教授 大江 浩一, 教授 中村 正治 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DGAM

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第22684号 / 理博第4625号 / 新制||理||1665(附属図書館) / 京都大学大学院理学研究科化学専攻 / (主査)教授 北川 宏, 教授 吉村 一良, 教授 有賀 哲也 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

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L’ifosfamide (IFO) et le cyclophosphamide (CPM) sont des oxazaphosphorines, prodrogues nécessitant une bioactivation pour être actif. Dans le cas de l’IFO, sa biotransformation conduit à une faible libération du composé hydroxylé actif accompagnée d’effets secondaires toxiques. Des analogues préactivés de l’IFO avec des chaines C1-C30 saturées ou non ont été développés, afin de contourner ces toxicités liées à la voie toxicogène du métabolisme. Dans le cadre de la stratégie de pharmacomodulation de l’IFO, l’évaluation cytotoxique de ces composés synthétisés a été réalisée in vitro sur des lignées cellulaires cancéreuses humaines. Une étude in vivo du Géranyloxy-IFO, un candidat potentiel, a démontré un meilleur profil pharmacocinétique pour le G-IFO comparativement à l’IFO. Ces analogues ont ensuite été vectorisés sous forme de nano-systèmes, soit par auto-assemblage ou par encapsulation lipidique constituant des vecteurs de 1ère génération. Ceux-ci continuent d’être développés afin de leur conférer une spécificité par ciblage passif ou actif.Par ailleurs, le CPM est connu pour son activité sur le système immunitaire à faible dose. Au vue de la proximité structurale entre l’IFO et el CPM, nous avons étudié l’effet immunomodulateur de l’IFO à faibles doses, en comparaison à la dose immunomodulatrice du CPM.La combinaison de ces deux stratégies (préactivation & effet immunomodulateur) pourrait conduire au développement de nouveaux dérivés démontrant une synergie antitumorale des effets antiprolifératif et immunomodulateur de ces oxazaphosphorines. / Ifosfamide (IFO) and cyclophosphamide (CPM) are oxazaphosphorines, prodrugs requiring bioactivation to be active. Regarding IFO, its biotransformation leads to a low release of the active hydroxylated compound with associated toxic side effects. Preactivated IFO analogs with saturated or unsaturated C1-C30 chains have been developed to circumvent these toxicities related to the toxicogenic pathway of metabolism. As part of IFO's pharmaco-modulation strategy, the cytotoxic evaluation of these compounds, synthesized by engraftment of poly-isoprenyloxy chains, was carried out in vitro on human cancer cell lines. In vivo study of the lead shows the better pharmacokinetic profile of Geranyloxy-IFO compared to IFO. These analogs were then vectorized as nanosystems, either by self-assembly or by lipidic encapsulation leading to 1st generation nanosystems. They are still under investigation in order to bring specificity by passive or active targeting.Furthermore, CPM is known for having an activity on the immune system at low dose. Due to the structural proximity of IFO and CPM, we fulfilled studies to highlight the effect of IFO on the immune system at low dose in comparison to the immunomodulatory dose of CPM.The combination of these two strategies (preactivation & immunomodulatory effect) could lead to the development of novel derivatives showing an antitumor synergy of the antiproliferative and immunomodulatory effects of these oxazaphosphorines.