ZnO is one of the most important materials for electronics, optoelectronics, piezoelectricity and optics. With a wide band gap of 3.37eV and an exiton binding energy of 60meV, ZnO 1D nanostructures exhibit promising properties in a lot of optical device applications. It is also an important piezoelectric material and has applications in a new category of nanodevices, nano-piezotronics. Demonstrated prototype of devices includes nanogenerators, piezoelectric-FET, and a series of evolutive devices based on the concept of nanogenerator. This is based on working principle of a semiconductor and piezoelectric coupled property. This thesis is about the growth, characterization and device fabrication of ZnO nanowires and nanobelts for sensors and UV detectors. First, the fundamental synthesis of ZnO nanostructurs is investigated, particularly polar surface dominated nanostructues, to illustrate the unique growth configurations of ZnO. Detail study in this part includes nanobelts, nanorings, nanocombs, nanonetworks, and nanodiskettes synthesis. Important factors in driving the nanostructure synthesis mechanism are analyzed, such as the chemical activities of different surface of ZnO and the polar surface dominated effects. Then, the devices fabricated methods using individual nanowires/nanobelts and their electrical transport properties were carefully characterized. In this part, dominant factors which are critical for nanobelt device performance are investigated, such as the contact properties, interface effects, and durability testing. Also, a metal doping method is studied to explore the controlling and modification of nanowire electric and optical properties. Further more, I will present the surface functionalization of nanobelt for largely improving its electrical, optoelectronic and chemical performance. Surface functionalization of nanobelts is proven to be an effective method in enhancing the semiconductor and metal contact. Piezoelectric field-effect transistors will be demonstrated as a powerful approach as chemical sensors. Finally, a technique is illustrated for functionalizing the surfaces of ZnO nanobelts for enhancing its UV sensitivity by over five orders of magnitude. This demonstrates an effective approach for fabricatiing ultrasensitive UV detectors. The research results presented in this thesis have made great contribution to the growth, device fabrication and novel applications of ZnO nanostructures for photonics, optoelectronics and sensors.

There are several studies in order to control drug delivery, decrease the toxicity of drugs and also for novel biomedical applications. It is necessary to be able to control the release of the drug within the body by using drug delivery systems. Mesoporous silica compounds have only been discovered twenty years ago and they have already attracted many researchers to study these materials for several applications. SBA-15 particles have a highly ordered regular structure and are a good matrix for guest-host applications. The aim of this study is to be able to address whether the surface functionalization of SBA-15 samples would improve the loading of a drug into these particles. The synthesized SBA-15 particles were surface functionalized by post - grafting synthesis method in order to be used as carrier materials for drug delivery. Amoxicillin was used as a model drug. These mesoporous materials have been characterized using X-ray diffraction (XRD), small-angle X-ray spectroscopy (SAXS), fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), N2 adsorption/ desorption, solid-state silicon nuclear magnetic resonance (Si-NMR), high-performance liquid chromatography (HPLC), ultra-violet (UV) spectroscopy, elemental and thermo gravimetric analysis (TGA). The effect of concentration difference and the type of alkoxysilanes used for the functionalization have been discussed in terms of loading amoxicillin and controlling the delivery. Drug delivery systems have many further applications that still need to be investigated in areas such as neurosciences, cancer and biomedical engineering.

Electrospun, non-woven, fibers have high surface area compared to conventional cast films. The thesis reports on the modification of electrospun fibers to concentrate and/or detect biohazards. In one study, electrospun fibers with affinity for the lectins ricin/concanavalin A were fabricated using molecular imprinting or through binding to immobilized antibodies, aptamers or lectin specific sugars. Attempts to fabricate imprinted electrospun fibers through inclusion of the template during the spinning process proved unsuccessful. However, electrospun fibers with affinity towards biohazards were successfully produced by post-modification with antibodies, aptamers or lectin specific saccharides. With regards to the latter, dextran, mannose and chitosan were immobilized onto nylon electrospun fibers that were partially hydrolyzed or treated with cyanuric chloride. The sugar-modified fibers bound significantly higher amount of lectins. Electrospun fibers were also fabricated, post modified with antibodies to capture and detect Salmonella. The study has illustrated the utility of electrospun fibers for biohazard diagnostics. / The National Center for Food Protection and Defense. USA

Urine culture, the current gold standard for urinary tract infection (UTI) diagnosis, does not produce results in an acceptable length of time. An ultra-sensitive, cost-effective electrochemical biosensing platform with nanostructured microelectrodes was designed to address the need for a rapid, point-of-care (PoC) test that could achieve a sample-to-answer time in less than an hour. Printed circuit boards and metallized glass slides were processed using various techniques and then tested for their ability to form nanostructured microelectrodes. Peptide nucleic acid probes for the bacteria and yeast as well as ten probes for antibiotic resistance genes were designed and synthesized for use with the new platform. Validation of the sensor's specificity was performed using high concentrations (100nM) of synthetic DNA oligomers. Furthermore, a clinically relevant sensitivity of 103 cfu/mL was demonstrated by detecting 4 pathogen lysates (Staphylococcus saprophyticus, Pseudomonas aeruginosa, Enterococcus faecalis and Klebsiella pneumoniae) in a buffered solution.

Urine culture, the current gold standard for urinary tract infection (UTI) diagnosis, does not produce results in an acceptable length of time. An ultra-sensitive, cost-effective electrochemical biosensing platform with nanostructured microelectrodes was designed to address the need for a rapid, point-of-care (PoC) test that could achieve a sample-to-answer time in less than an hour. Printed circuit boards and metallized glass slides were processed using various techniques and then tested for their ability to form nanostructured microelectrodes. Peptide nucleic acid probes for the bacteria and yeast as well as ten probes for antibiotic resistance genes were designed and synthesized for use with the new platform. Validation of the sensor's specificity was performed using high concentrations (100nM) of synthetic DNA oligomers. Furthermore, a clinically relevant sensitivity of 103 cfu/mL was demonstrated by detecting 4 pathogen lysates (Staphylococcus saprophyticus, Pseudomonas aeruginosa, Enterococcus faecalis and Klebsiella pneumoniae) in a buffered solution.

Actuellement, les recherches sur la fonctionnalisation des surfaces sont en pleine effervescence. Dans ce manuscrit, nous proposons une approche innovante pour mesurer l’efficacité de cette fonctionnalisation. Cette approche est basée sur l’utilisation d’un microscope à force atomique, opérant dans un mode dit de « modulation de fréquence ». Cet outil couplé aux pointes greffées d’un nanotube de carbone, que nous appellerons « sonde », permet d’obtenir des mesures qu’il serait impossible d’effectuer avec des pointes standards. En métrologie, afin d’assurer une bonne reproductibilité des mesures, nous avons besoin d’avoir des sondes ayant des caractéristiques les plus similaires possibles. Ceci a nécessité la mise en oeuvre d’une méthode pour optimiser la fabrication des sondes, ainsi qu’une définition de critères pour les classer dans différents grades de qualités. L’incertitude de répétabilité et de reproductibilité des mesures effectuées avec des sondes de grade « A » a été quantifiée. Ces mesures ont démontré que ces sondes sont compatibles en termes de robustesse et de sensibilité pour la caractérisation de surfaces fonctionnalisées, dont l’épaisseur est supérieure à la monocouche. Des mesures de cartographie effectuées sur de deux types de surfaces fonctionnalisées ont permis de dissocier la mesure de topographie de la réponse mécanique du nanotube en interaction avec la surface. / At present, the researches on the surface functionalization are in full effervescence. In this manuscript, we propose an innovative approach to measure the efficiency of this functionalization. This approach is based on the use of an atomic force microscope, operating in a mode called "frequency modulation". This tool coupled with the grafted tips with a carbon nanotube, which we will call "probe", allows to obtain measurements which would be impossible to make with standard tips. However, in metrology, in order to ensure good reproducibility of the measurements, we need to have probes with characteristics that are as similar as possible. This required the implementation of a method to optimize the manufacture of the probes, as well as a definition of criteria to classify them in different grades of qualities. The uncertainty of repeatability and reproducibility of the measures made with probes of rank "A" were quantified. These measurements have demonstrated that these probes are compatible in terms of robustness and sensitivity for the characterization of functionalized surfaces, whose thickness is superior to the monolayer. Mapping measurements carried out on two types of functionalized surfaces enable to dissociate the topography measurement from the mechanical response of the nanotube in interaction with the surface.

Tumores de mama podem ser categorizados pela expressão de diferentes receptores, como por exemplo o HER-2 (receptor de fator de crescimento epidérmico 2), sendo amplamente estudada a utilização do fármaco inibidor do receptor da tirosina–quinase, ditosilato de lapatinib. Nesse sentido, o trabalho está centrado no desenvolvimento farmacotécnico e caracterização físico-química de nanocápsulas multiparede revestidas com polissorbato 80 e fosfatidilcolina (LIPOID S75®), seguidas de revestimento com quitosana, contendo ditosilato de lapatinib (25μg/mL e 50μg/mL). Estudos físico-químicos da fase orgânica e das nanocápsulas contendo LIPOID S75®, em diferentes concentrações, foram desenvolvidos através de medidas de viscosidade, tensão superficial e analise de calorimetria exploratória diferencial, correlacionando com o tamanho de partícula e interação da fosfatidilcolina no sistema. A partir disso, escolheu-se a maior concentração de LIPOID S75® testada, para desenvolver as nanocápsulas multiparede complexadas com metal e fenilalanina contendo ditosilato de lapatinib (Lap25-P5-Q-Fe-Phe; Lap50-P5-Q-Fe-Phe; Lap25-P5-Q-Zn-Phe; Lap50-P5-Q-Zn-Phe). As formulações contendo fármaco apresentaram distribuição unimodal de partículas na faixa nanométrica, (111 - 172 nm) e baixo índice de polidispersão. A faixa de potencial zeta obtida (+16 - +22 mV) indicou o revestimento da partícula pela quitosana. O ditosilato de lapatinib foi quantificado por cromatografia líquida de alta eficiência (HPLC). A fase móvel do método consistiu em acetonitrila:acetato de amônio 0,02M (70:30), vazão de 1,0 mL/min com detecção em 260 nm. As suspensões contendo 25 μg/mL e 50 μg/mL de fármaco apresentaram teor entre 93% e 91%, respectivamente. A eficiência de encapsulação (EE%) foi acima de 90%. O conjunto destes estudos demonstra que nanocápsulas desenvolvidas são potenciais candidatas para ensaios biológicos in vitro. / Breast tumors may be categorized by the expression of different receptors such as HER-2 (growth factor epidermal receptor 2), The use of the inhibitor drug receptor tyrosine-kinase lapatinib ditosylate (Tyverb®, GlaxoSmithKline) has been widely studied. In this sense, the work is focused on pharmaceutics development and physicochemical characterization of multiwall nanocapsules coated with polysorbate 80 and phosphatidylcholine (Lipoid S75®), followed by coating with chitosan containing lapatinib ditosylate (25 μ/mL and 50 μg/mL). Physicochemical studies of the organic phase and nanocapsules containing Lipoid S75® at different concentrations were developed by viscosity, surface tension analysis and differential scanning calorimetry, correlated with the particle size and interaction of phosphatidylcholine in the system From this, we have chosen the highest concentration of lipoid S75® tested to develop complexed nanocapsules multiparede with metal and phenylalanine containing lapatinib ditosylate (Lap25-P5-Phe-Phe-Q; Lap50-P5-Q -Fc-Phe; Lap25-P5-O-Zn-Phe; Lap50-P5-Zn-O-Phe). Formulations containing lapatinib ditosylate showed unimodal distribution of particles in the nanometer range (111-172 nm) and low polydispersity index. The obtained zeta potential range (+16 - +22 mV) indicated by the chitosan particle coating. The lapatinib ditosylate was quantified by high-performance liquid chromatography (HPLC). The mobile phase consisted method in acetonitrile: 0.02M ammonium acetate (70:30), flow 1.0 mLmin-1 with detection at 260 nm. The suspensions containing 25 ugmL-1 and 50 ugmL-1 showed drug content of between 93% and 91%, respectively. The encapsulation efficiency (EE%) was above 90%. Together these studies demonstrate that the nanocapsules are potential candidates for in vitro biological assays.

L’analyse des radionucléides est une nécessité pour la gestion des matières et déchets radioactifs liée à l’industrie nucléaire. Pour éviter les interférences et améliorer la précision des mesures, les étapes de traitement de l’échantillon et de séparations restent aujourd’hui incontournables. Elles sont cependant longues, irradiantes, difficiles à mettre en œuvre en boite à gants et produisent un volume de déchets liquides et solides significatif. L’objectif de cette thèse est de proposer une alternative innovante à l’utilisation des colonnes d’extraction sur phase solide dans les protocoles de séparation des radionucléides en milieu nitrique concentré permettant de réduire ces déchets en fin de cycle analytique et d’automatiser ces étapes. Un premier microsystème jetable en plastique (COC) intégrant une micro-colonne séparative de chromatographie d’extraction a été conçu. La phase stationnaire est un monolithe poly(AMA-co-EDMA) synthétisé par photopolymérisation in situ à structure ajustable, fonctionnalisable à façon, résistant au milieu nitrique concentré. Les capacités d’échange obtenues sont de l’ordre de 150 mgU/g de monolithe pour le TBP et le mélange TBP/CMPO et 280 mgU/g de monolithe pour le DAAP. Les valeurs des coefficients de partage des monolithes imprégnés ont été déterminées pour U(VI), Th(IV), Eu(III) et Nd(III) pour les 3 extractants (ainsi que pour Pu(IV) dans le cas de monolithes imprégnés par le TBP). La synthèse du monolithe a été transférée en microsystème centrifuge et après étude hydrodynamique, la séparation U,Th/Eu en milieu nitrique a été réalisée sur colonne imprégnée TBP en microsystème classique puis transférée en microsystème centrifuge. / Radionuclides analysis is a key point for nuclear waste management and nuclear material control. Several steps of sample modification have to be carried out before measurements in order to avoid any interferences and improve measurement precision. However those different steps are long, irradiant and difficult to achieve in gloveboxes. Moreover they produce liquid and solid waste. The goal of the study is to offer a new alternative to the use of solid phase extraction column for radionuclides separation in hard nitric acid medium. The system will decrease the amount of nuclear waste due to the analysis and automatize the different steps of the analysis. A plastic device made of COC containing a micro solid phase extraction column is first designed. Stationary phase is a poly(AMA-co-EDMA) monolith synthetized in situ. Its structure is adjustable and its functionalization versatile with a high resistance to nitric acid medium. Exchange capacity is 150 mg/g of monolith for TBP and TBP/CMPO column and up to 280 mg/g of monolith in case of DAAP. Exchange coefficients are determined for U(VI), Th(IV), Eu(III) and Nd(III) for 3 different extractants (and Pu(IV) in case of TBP column). Monolith synthesis is transferred in centrifugal device and hydrodynamic behavior studied. U,Th/Eu separation was finally carried out in both classic and centrifugal microsystem on TBP column.

Tumores de mama podem ser categorizados pela expressão de diferentes receptores, como por exemplo o HER-2 (receptor de fator de crescimento epidérmico 2), sendo amplamente estudada a utilização do fármaco inibidor do receptor da tirosina–quinase, ditosilato de lapatinib. Nesse sentido, o trabalho está centrado no desenvolvimento farmacotécnico e caracterização físico-química de nanocápsulas multiparede revestidas com polissorbato 80 e fosfatidilcolina (LIPOID S75®), seguidas de revestimento com quitosana, contendo ditosilato de lapatinib (25μg/mL e 50μg/mL). Estudos físico-químicos da fase orgânica e das nanocápsulas contendo LIPOID S75®, em diferentes concentrações, foram desenvolvidos através de medidas de viscosidade, tensão superficial e analise de calorimetria exploratória diferencial, correlacionando com o tamanho de partícula e interação da fosfatidilcolina no sistema. A partir disso, escolheu-se a maior concentração de LIPOID S75® testada, para desenvolver as nanocápsulas multiparede complexadas com metal e fenilalanina contendo ditosilato de lapatinib (Lap25-P5-Q-Fe-Phe; Lap50-P5-Q-Fe-Phe; Lap25-P5-Q-Zn-Phe; Lap50-P5-Q-Zn-Phe). As formulações contendo fármaco apresentaram distribuição unimodal de partículas na faixa nanométrica, (111 - 172 nm) e baixo índice de polidispersão. A faixa de potencial zeta obtida (+16 - +22 mV) indicou o revestimento da partícula pela quitosana. O ditosilato de lapatinib foi quantificado por cromatografia líquida de alta eficiência (HPLC). A fase móvel do método consistiu em acetonitrila:acetato de amônio 0,02M (70:30), vazão de 1,0 mL/min com detecção em 260 nm. As suspensões contendo 25 μg/mL e 50 μg/mL de fármaco apresentaram teor entre 93% e 91%, respectivamente. A eficiência de encapsulação (EE%) foi acima de 90%. O conjunto destes estudos demonstra que nanocápsulas desenvolvidas são potenciais candidatas para ensaios biológicos in vitro. / Breast tumors may be categorized by the expression of different receptors such as HER-2 (growth factor epidermal receptor 2), The use of the inhibitor drug receptor tyrosine-kinase lapatinib ditosylate (Tyverb®, GlaxoSmithKline) has been widely studied. In this sense, the work is focused on pharmaceutics development and physicochemical characterization of multiwall nanocapsules coated with polysorbate 80 and phosphatidylcholine (Lipoid S75®), followed by coating with chitosan containing lapatinib ditosylate (25 μ/mL and 50 μg/mL). Physicochemical studies of the organic phase and nanocapsules containing Lipoid S75® at different concentrations were developed by viscosity, surface tension analysis and differential scanning calorimetry, correlated with the particle size and interaction of phosphatidylcholine in the system From this, we have chosen the highest concentration of lipoid S75® tested to develop complexed nanocapsules multiparede with metal and phenylalanine containing lapatinib ditosylate (Lap25-P5-Phe-Phe-Q; Lap50-P5-Q -Fc-Phe; Lap25-P5-O-Zn-Phe; Lap50-P5-Zn-O-Phe). Formulations containing lapatinib ditosylate showed unimodal distribution of particles in the nanometer range (111-172 nm) and low polydispersity index. The obtained zeta potential range (+16 - +22 mV) indicated by the chitosan particle coating. The lapatinib ditosylate was quantified by high-performance liquid chromatography (HPLC). The mobile phase consisted method in acetonitrile: 0.02M ammonium acetate (70:30), flow 1.0 mLmin-1 with detection at 260 nm. The suspensions containing 25 ugmL-1 and 50 ugmL-1 showed drug content of between 93% and 91%, respectively. The encapsulation efficiency (EE%) was above 90%. Together these studies demonstrate that the nanocapsules are potential candidates for in vitro biological assays.

Engineering of biofunctional scaffolds to precisely regulate cell behavior and tissue growth is of significance in regenerative medicine. Protein-based biomaterials are attractive candidates for functionalization of scaffold surfaces since the ability to precisely control protein sequence and structure allows for fine-tuning of cell-substrate interactions that regulate cell behavior. In this thesis, a series of de novo proteins for bio-functionalization of interfaces was designed, synthesized, and studied. These proteins are based on a diblock motif consisting of a surface-active, amphiphilic block β-sheet domain linked to a disordered, water-soluble block with a terminal functional domain. Several types of functional domains were investigated, including sequences that act as ligands for cell surface receptors and sequences that act as templates for the growth of inorganic particles. Under moderate temperature and pH conditions, the amphiphilic β-sheet block was shown to have a strong affinity to a variety of scaffold materials and to form stable protein coatings on hydrophobic materials by self-assembly. Moreover, the surface adsorption of the proteins was shown to have minimal impact on the presentation of the functional end domains in the soluble block. For the case of diblocks with the RGDS integrin binding sequence, the capability for mediating cell attachment and spreading was demonstrated via control over ligand density on hydrophobic polymer surfaces. The case of diblock proteins with templating domains for inorganic materials was investigated for two systems. First, hydroxyapatite-binding domains were ligated to the end terminus of the water-soluble block to develop proteins for possible bone regeneration applications. It was demonstrated that the hydroxyapatite-binding domain had strong affinity to hydroxyapatite nanoparticles and was able to induce calcium phosphate mineralization on the surfaces coated with diblock proteins from dilute solutions with Ca2+.and PO43-. Next, a silver-binding domain was ligated to the end terminus to create a diblock protein for potential antimicrobial surface applications. The silver-binding domain was shown to accumulate and reduce silver ions, resulting in the formation of silver nanoparticles on the surfaces functionalized by the protein.