L’utilisation de nanoparticules (NPs) dans un milieu biologique est de plus en plus importante, alors que leur assimilation et leur toxicité reste peu maitrisée. Dans ce contexte l’objectif de ce travail est d’étudier l’interaction entre nanoparticules de dioxyde de titane (TiO2) avec des protéines ainsi que leur possible impact sur leurs propriétés structurales. Trois protéines d’intérêt ont été choisies: une protéine de la matrice extra cellulaire, le collagène, et deux protéines du plasma sanguin, l’albumine et le fibrinogène. Le choix a été basé sur l’importance biologique de ces protéines lors des interactions avec des NPs et sur la différence de leurs structures tridimensionnelles. L’étude de l’interaction protéine-NPs a été réalisée en solution et en phase adsorbée dans différentes conditions de température et de temps d’incubation. Dans un premier temps des nanoparticules de dioxyde de titane ont été synthétisées par voie solvothermale, afin d’obtenir des nanoparticules de tailles et de formes contrôlées. Deux types de nanoparticules ont été sélectionnés en vues d’étudier l’effet de forme et de taille sur l’interaction protéines-nanoparticules: des nano-sphères de diamètre de 8 à 10 nm et des nano-bâtonnets d’environ 8 nm de largeur et 23 nm longueur. Leur comportement en solution physiologique ainsi que leur réactivité ont été caractérisé par DSL et absorption UV montrant une inhibition des propriétés catalytiques ainsi qu’une forte agrégation en solution tampon phosphate saline (PBS). Dans un deuxième temps les propriétés d’adsorption du collagène en présence de nanoparticules furent étudiées sur deux types de surfaces l’une hydrophobe et l’autre hydrophile par XPS et imagerie AFM ainsi que par des mesures de forces AFM. Le comportement du collagène en solution en présence de nanoparticules a été caractérisé par ATR liquide. Les observations suggèrent que la formation des fibrilles à l’interface surface-solution de collagène est affectée par le caractère hydrophobe ou hydrophile de la surface ainsi que par la présence de nanoparticules. Enfin les propriétés d’adsorption de la HSA et du fibrinogène en présence de nanoparticules furent étudiées sur une surface hydrophile par imagerie AFM et analyses XPS. Leur comportement en solution en présence de nanoparticules fut étudié par ATR liquide. Les résultats suggèrent deux comportements différents des protéines en présence de nanoparticules pouvant être attribués propriétés physicochimiques différentes des protéines. La HSA subit d’importants changements structuraux en présence de nanoparticules contrairement au fibrinogène.L’étude en phase liquide de l’interaction protéine-nanoparticules couplé à l’étude en phase adsorbées des protéines permet de déterminer les phénomènes impliqués lors de cette interaction ainsi que leurs conséquences sur les protéines, de plus l’utilisation de nanoparticules de taille et forme différentes permet d’étudier la sensibilité des protéines à ces facteurs. / The extensive use of NPs in a biological environment raises the problem of their assimilation or their toxicity, the main objective of this work is to study the interaction of TiO2 NPs with proteins as well as their possible impact on the structural properties of proteins. Three proteins were chosen, a protein of the extracellular matrix, the collagen, and two proteins of the plasma blood, the albumin and the fibrinogen for their biological importance as well as for their various tridimensional structures. The study of the protein-nanoparticle interaction was realized in solution and in the adsorbed phase under various condition of temperature and incubation time. First, titanium dioxide NPs were synthesized by a solvothermal method, NPs with controlled size and form were obtained. Two types of NPs were selected in order to study the effect of shape and size on the protein-NPs interaction: nano-spheres with a diameter of 8 to 10 nm and nano-rods with a width about 8 nm and a length of 23 nm. The behavior in physiological solution as well as the reactivity were characterized by DSL and UV absorption showing an inhibition of catalytic properties as well as a strong aggregation in phosphate buffer saline solution (PBS). Second, the adsorption properties of the collagen in the presence of NPs were studied on two kinds of surfaces, one hydrophobic and the other hydrophilic by XPS and AFM imaging as well as by AFM force measurements. The behavior of the collagen in solution in the presence of NPs was characterized by liquid ATR. The observations suggest that the formation of fibrils at the surface- collagen solution interface is affected by the hydrophobic or the hydrophilic character of the surface as well as by the presence of NPs. In the last part the adsorption properties of HSA and fibrinogen in the presence of NPs were studied on a hydrophilic surface by AFM imaging and XPS analyses. Their behaviors in solution in the presence of NPs were studied by liquid ATR. The results suggest two different behaviors of proteins in the presence of NPs, which can be attributed to the different physico-chemical properties of the proteins. HSA undergoes important structural changes in the presence of NPs but not fibrinogen. The study in the liquid phase of the protein-nanoparticle interaction, coupled to study of proteins in the adsorbed phase allows determining the involved phenomenon during the protein-nanoparticle interaction as well as the consequences on protein adsorption. Moreover, the use of NPs with different sizes and shapes revealed the sensitivity of proteins to these factors.

Sample preparation is the most time-consuming and error-prone step in chemical analysis. Miniaturization and automation of the sample preparation equipment eliminating or reducing the use of hazardous organic solvents, online hyphenation of sample preparation with analytical instruments in a cost-effective way are important factors that need to be considered to design and implement innovative sample preparation techniques and strategies. Solid-phase microextraction (SPME) is a simple, environmentally benign technique well suited for hyphenation with analytical instruments. However, poor coating stability is a significant drawback of SPME employing conventionally prepared coatings. This shortcoming arises from the lack of chemical bonding between the sorbent coating and the substrate. Introduction of sol-gel coatings in SPME greatly improved thermal stability and solvent stability in SPME, by providing direct chemical bonding between substrate and the sol-gel coating. In traditional fiber format of SPME (where the sorbent coating is placed on the outer surface of an end-segment of the fiber) the coating remains vulnerable to mechanical damage. Capillary microextraction (CME), the capillary format of SPME (also known as in-tube SPME), allows to overcome this shortcoming by securing the sorbent coating on inner walls of the capillary. This dissertation focuses on the development and systematic investigation of novel silica- and germania-based perfluorinated and non-fluorinated sol-gel sorbents in the form of CME surface coatings: their preparation, material characterization, CME performance evaluation, preconcentration and recovery of various analytes including environmental pollutants. This research established that germania-based sol-gel sorbents are characterized by superior microextraction performance than analogous silica-based sorbents. This enhanced performance provided by germania-based sol-gel sorbents may be explained based on thermogravimetric analysis suggests that higher carbon loading on germania-based sol-gel sorbents. Germania-based phenyl- (Ph), phenethyl- (PhE), octyl- (C8), octadecyl- (C18) and cyclohexenylethyl- (ChE) ligand-containing sol-gel sorbents were prepared and various pollutants with aromatic rings (such as aromatic ketones, aldehydes and polycyclicaromatic hydrocarbons) were extracted and analyzed by CME-GC and CME-HPLC. It was observed that sol-gel sorbents containing aromatic ligands (PhE and Ph) provided superior microextraction performance for the analytes with aromatic ring(s) in their structure, than the sorbents with aliphatic ligands (C8 and C18). Investigation of sol-gel sorbents containing hydrophobic perfluorooctyl (PF-C8) and perfluorododecyl (PF-C12) ligands revealed that PF-C8 and PF-C12 sol-gel sorbents provided ~ 3 times higher microextraction efficiency (measure in terms of specific extraction, SE) than corresponding non-fluorinated counterparts, C8- and C12-, respectively. The synthesis and design of silica- and germania-based dual ligands sol-gel sorbents simultaneously providing superhydrophobicity and π-π interactions with analytes represent a significant accomplishment of this research. Such sorbents contained a PF-C12 and PhE ligands incorporated in sorbent chemical structure. In this case, perfluoro- group provided enhanced hydrophobic interaction and PhE group provided π-π interaction with the analytes. Combination of such interactions proved to be quite effective in the microextraction of alkylbenzenes and related compounds. Dual-ligand sol-gel sorbents with both equimolar and non-equimolar ligand concentrations were prepared. Experimentally it was established that sorbents with higher perfluorinated alkyl ligand concentrations had higher affinity for aliphatic hydrocarbons; however; when PhE concentration was higher, the dual-ligand sorbent showed enhanced affinity for aromatic compounds. The prepared sol-gel sorbents were characterized by less than 5% run-to-run RSD values, and also less than 5% capillary-to-capillary RSD values, which indicate that the sol-gel technique used in sorbent preparation was highly reproducible. The prepared sol-gel sorbents also showed that their performance does not deteriorate under aqueous saline matrix; therefore, it could be useful in the microextraction of pollutants from ocean water.

Des revêtements antiréflectifs hydrophobes à bas indice de réfraction ont été synthétisés sous forme de couches minces nanométriques de silice mésoporeuses par chimie sol gel couplée à un procédé de dépôt par dip coating sur substrats polymériques thermosensibles de polyméthacrylate de méthyle (PMMA) et de triacétate de cellulose (TAC). Les couches minces de silice pure et hybride ont été durcies par traitement en vapeur d’ammoniaque (TVA) à température ambiante. Les propriétés optiques, mécaniques et de résistance chimique des revêtements ont été optimisées et des mécanismes décrivant les modifications de la structuration induit par TVA selon la composition chimique des films ont été proposés grâce à l’étude de l’influence des conditions et des temps de traitement en vapeur d’ammoniaque. La condensation et la stabilisation de vapeur d’eau à l’intérieur de films de silice mésoporeux hydrophobes à l’aide de vapeur d’alcool ont été réalisées à température et pression ambiantes. L’étude de l’influence de la chimie de surface, de la taille des pores ainsi que des pressions partielles en eau et alcool, et de la nature du co-adsorbant alcoolique a permis de mettre en lumière les mécanismes d’adsorption et de confinement d’eau dans des nano-cavités hydrophobes. La diffusion d’eau à l’intérieur de monolithes de xérogel de silice millimétriques a été rapportée en utilisant pour la première l’ellipsométrie environnementale in situ. Des sujets aussi variés que la réalisation de films à gradient de fonctionnalité, la fabrication d’actuateurs sensibles à l’humidité à partir de films minces inorganiques, la synthèse de couches minces mésostructurées de BaTiO3 et la mise de forme 3D de films de quartz sont discutés dans ce manuscrit. / Low refractive index hydrophobic antireflective coatings were synthetized as mesoporous nanometric thin silica films by use of sol gel chemistry coupled with the dip coating process on thermo sensitive polymeric substrates such as poly(methyl methacrylate) (PMMA) and cellulose triacetate (TAC). Thin films of pure and hybrid silica were stiffened by ammonia vapor treatment (AVT) at room temperature. Optical, mechanical and chemical stability of those coatings were optimized and the AVT-induced mechanisms of structuration depending on the chemical composition of silica films were proposed after the study of the influence of the ammonia treatment conditions and duration. Alcohol-assisted water vapor condensation and stabilization in hydrophobic mesoporous silica thin films were displayed at room temperature and atmospheric pressure. Study of the influence of surface chemistry and pore size, as well as partial vapor pressure of water and alcoholic co-adsorbant, and chemical nature of the alcohol allowed us to determine the mechanisms of water adsorption and confinement in hydrophobic nano-cavities. Water diffusion into millimetric scaled silica xerogel monoliths was reported using in situ environmental ellipsometry for the first time. Other subject as different as the production of graded functional films, fabrication of inorganic thin films based humidity sensitive actuators, synthesis of BaTiO3 mesostructured thin films and shaping of 3D quartz films are also discussed.

Sick building syndrome (SBS) is a particular concern in places with inadequate ventilation and frequently attributed to chemical contaminants such as volatile organic compounds (VOCs)released from indoor sources that are frequently encountered in everyday life such as adhesives, carpeting, upholstery, manufactured wood products, copy machines, pesticides, cleaning agents inside buildings, plumbing vents, and painting. Furthermore, it is a major issue for modern human beings who spend most of their time indoors or must stay indoors for self-isolation due to special circumstances such as the coronavirus disease-19 (COVID-19) pandemic that occurred in 2019 and 2020. Main indoor VOCs are trichloroethylene (TCE), benzene, toluene, and para-xylene (p-xylene). In general, these compounds are not present in indoor spaces at acute concentrations, but prolonged exposure to these compounds can have chronic health effects such as allergic sensitization, increased cancer risks, and respiratory diseases. In this study, the adsorption process with various advantages has been applied to remove VOC’s using commercially available hydrophobic adsorbents. The hydrophobic adsorbents can contribute to reducing the possibility of chemical adsorption (chemisorption) of moisture from the air, which can decrease the capacity of adsorbent by clogging the pores. The adsorption of these major VOCs was investigated in this work for three major types of industrial hydrophobic adsorbents: activated carbons, zeolites, and polymer. This study will show the investigation into finding the most promising hydrophobic adsorbent for removal of TCE, benzene, toluene, and p-xylene, which are the main VOCs found indoors. The promising hydrophobic adsorbent has been determined by comparing Henry’s law constants and heat of adsorption values for the different adsorbents, which were estimated by using a concentration pulse chromatographic technique by utilizing a gas chromatograph equipped with a flame ionization detector. For all adsorbents, Henry’s law constants at room temperature of p-xylene were always the highest followed by toluene, benzene, and TCE. For all adsorbates, Henry’s law constants at room temperature of AC BPL and HiSiv 3000 were higher than the other hydrophobic adsorbents. For a developing modern society dealing with a pandemic, this study can contribute to producing the optimized gas masks and indoor filters for the removal of indoor air pollutants, which can help people who suffer from SBS. It can also help society for taking preventative actions towards dealing with SBS.

This study experimentally investigated the effect of hydrophobic and hydrophilic surfaces characteristics on nucleate boiling heat transfer performance for the application of direct immersion cooling of electronics. A dielectric liquid, HFE – 7100 was used as the working fluid in the saturated boiling tests. Twelve types of 1-cm2 copper heater samples, simulating high heat flux components, featured reference smooth copper surface, fully and patterned hydrophobic surface and fully and patterned hydrophilic surfaces. Hydrophobic samples were prepared by applying a thin Teflon coating following photolithography techniques, while the hydrophilic TiO2 thin films were made through a two step approach involving layer by layer self assembly and liquid phase deposition processes. Patterned surfaces had circular dots with sizes between 40 – 250 μm. Based on additional data, both hydrophobic and hydrophilic surfaces improved nucleate boiling performance that is evaluated in terms of boiling incipience, heat transfer coefficient and critical heat flux (CHF) level. The best results, considering the smooth copper surface as the reference, were achieved by the surfaces that have a mixture of hydrophobic/hydrophilic coatings, providing: (a) early transition to boiling regime and with eliminated temperature overshoot phenomena at boiling incipience, (b) up to 58.5% higher heat transfer coefficients, and (c) up to 47.4% higher CHF levels. The studied enhanced surfaces therefore demonstrated a practical surface modification method for heat transfer enhancement in immersion cooling applications.

This thesis deals with the aggregation behaviour of palmitoylhyaluronan in two degrees of substitution, namely 10 % and 16 %. Using a fluorescence spectroscopy method with pyrene as a fluorescence probe, we found a critical micellar concentration. The results were confirmed by measuring the dynamic light scattering, which also showed an increase in the size of aggre-gates with an increasing concentration. System stability is reduced by increased ionic strength as evidenced by zeta potential measurement. Experiments found that 16 % substitution sample can form a gel. The gel is very stiff and has excellent properties, which was confirmed by rhe-ology. We also managed to incorporate pyrene in the gel, which was demonstrated by the presence of highly solvated domains that could be polymer micelles. Based on these results, 16% substitution sample was subjected the MTT assay to cytotoxicity. The results confirmed that the examined sample was not toxic.

The textile industry is a big environmental polluter, with one of the biggest concerns being water pollution and usage. This necessitates resource efficient methods for wet textile processes. To reduce the resources used during wet textile processing, a novel technology was researched in this thesis to dye and hydrophobic finish wool in a one-step process. Two different wool fabrics were exhaust dyed and pad finished as a conventional method to compare to dyeing and finishing in a two-step and one-step process with a hydraulic spray atomising system. In all three processes, acid and reactive dyes were used for dyeing and hyperbranched polymers, i.e. dendrimers, were used for hydrophobic finishing. To test the colour and hydrophobicity fastness, washing and abrasion tests were done on the samples of all three processes. It was found that there is a big colour difference between the conventional and hydraulic spray method, where the colour is less strong in the hydraulic spray method. This has to do with the difference in the dye fixation step, where in the conventional method, the dye fixation happens in an aqueous medium, and in the hydraulic spray this happens in a nonaqueous medium. The hydrophobicity is however significantly better in the samples finished in the hydraulic spray, as this is rather a surface treatment. The results in colour and contact angle between the two-step and one-step process did not significantly change, so it can be concluded that it is possible to combine dyeing and finishing in the hydraulic spray method. The colour and hydrophobic fastness to abrasion and washing is significantly worse for the samples of the hydraulic spray method compared to the conventional method. The hydraulic spray method can still be optimised to overcome problems with colour and fastness, however this is future work. The hydraulic spray method uses significantly less water, chemicals and energy in a two-step process, and even more in a one-step process. Therefore, it has the potential to reduce the use of water, chemicals and energy in wet textile processing, for all types of fibres, and thus strongly contribute to a more environmental conscious wet textile process.

This thesis is concerned with the fate of hydrophobic organic pollutants (HOCs) in soil. The theoretical part summarizes the current knowledge about bioavailability, factors influencing the bioavailability and methods for its measurement. Attention is paid to the organic carbon content, which is considered to be one of the key factors and to the influence of microorganisms that can degrade or interact with the substances, thus changing their bioavailable ratio. The practical part of the thesis uses bioaccumulation test with earthworm Eisenia andrei for evaluating the uptake kinetics HOCs in three soils with different organic carbon content. Soils were laboratory contaminated with mixtures of selected HOCs (phenanthrene, pyrene, lindane, p,p'-DDT and PCB 153) and the concentrations of substances in these soils were followed for 217 days. Subsequently, bioaccumulation test was conducted; earthworms were exposed from one to twenty-one days. The collected data were used to model uptake kinetics curves for individual substances. Peak-shaped bioaccumulation were found for pyrene, for lindane a steady-state concentration during exposure was observed, whereas for p,p'-DDT and PCB 153 growing concentrations after twenty days of exposure were detected. The reason for the different behavior of the substances was probably their diverse sorption on the organic material, which together with the different speed of elimination influenced final concentration in earthworms. Phenanthrene was not detected in some samples and therefore the modeling of uptake kinetics was not possible.

El polidimetilsiloxano (PDMS) es un polímero amorfo en base inorgánica con grupos pendientes que le imparten hidrofobicidad que es ampliamente utilidado en aplicaciones biomédicas. Debido a la baja energía superficial del PDMS, su adhesión es pobre. En algunas aplicaciones biomédicas (catéteres, prótesis) se requiere adhesión para lo cual se modifica superficialmente. Los plasmas generados en condiciones de no-equilibrio, también llamados plasmas fríos, han sido utilizados en el tratamiento superficial de PDMS para aumentar su energía superficial, pero las modificaciones producidas son poco estables, produciéndose una rápida recuperación de la hidrofobicidad (hydrophobic recovery). La estabilidad de las modificaciones superficiales del PDMS depende de las características del plasma utilizado para su tratamiento, por lo que el objetivo de la tesis doctoral se centra en la utilización de diferentes tipos de plasmas fríos para modificar las propiedades superficiales de PDMS de manera que simultáneamente se aumente su estabilidad y se mejore su adhesión. Otro aspecto innovador en el estudio consiste en la discriminación y optimización de las condiciones de tratamiento con plasma utilizando un diseño estadístico de experimentos, lo que he permitido modelar el efecto del tratamiento con plasma de superficies de PDMS empleando los ángulos de contacto y la química superficial como variables respuesta. Se ha estudiado el efecto de los diferentes tipos de plasma en la hidrofobicidad y la energía superficial del PDMS mediante medidas de ángulo de contacto. Las modificaciones en la química superficial han sido evaluadas usando espectroscopia infrarroja en modo de reflectancia total atenuada (FTIR-ATR) y espectroscopia fotoelectrónica de rayos X (XPS), mientras que los cambios en la morfología y nanorugosidad superficial se monitorizaron usando microscopía electrónica de barrido (SEM) y microscopía de fuerza atómica (AFM). Las propiedades de adhesión del PDMS se evaluaron mediante ensayos de adhesión en pelado en T y de cizalla a solape simple, utilizando un adhesivo sensible a la presión (PSA) en base acrílica para uso médico. Estas propiedades fueron además monitorizadas en función del tiempo tras el tratamiento con plasma para determinar la estabilidad de las modificaciones producidas. En general, el tratamiento superficial de PDMS con plasma produce oxidación de las cadenas de polisiloxano por sustitución de los grupos metilo por grupos hidroxilo, lo que aumenta la polaridad y la energía superficial, incrementando las propiedades de adhesión. Se produce el entrecruzamiento de cadenas mediante condensación de los grupos hidroxilo, formando una delgada capa superficial con estructura de sílice. Cuando las características del plasma son demasiado agresivas aparecen grietas superficiales favoreciendo la recuperación hidrofóbica por difusión de especies apolares desde el seno del PDMS hacia la superficie, así como por la reorientación de los nuevos grupos polares en la superficie hacia el seno del material. Este fenómeno se minimiza optimizando las condiciones de tratamiento empelando un diseño estadístico de experimentos. En sistemas de generación de plasma a baja presión, tratamientos con baja potencia durante largos tiempos mejoran la funcionalización de la superficie del PDMS, y el uso de mezclas de argón y oxígeno como gas plasmógeno resulta más efectivo que el empleo de los gases puros; la presión de trabajo tiene un papel fundamental en la estabilidad de las modificaciones producidas. En sistemas de antorcha de plasma atmosférico el tiempo de tratamiento y la distancia de la boquilla a la superficie son los parámetros más relevantes en la oxidación superficial del PDMS, mientras que en sistemas de plasma atmosférico de doble barrera dieléctrica, el voltaje, el tiempo de tratamiento y la distancia entre electrodos son las variables críticas en la efectividad del tratamiento superficial. Finalmente, la deposición de monómeros mediante antorcha de plasma permite generar nanoestructuras superficiales en el PDMS aportándole características de superhidrofobicidad.

No description available.