The use of desiccant materials is crucial in many applications, such as dehumidification rotors, in OLED screen and as desiccant materials in dish washers, for example. Upsalite® is a novel, anhydrous, micro-mesoporous, and large surface area structure consisting of amorphous magnesium carbonate which has been shown to exhibit a good water sorption capacity. Depending on the heat treatment of Upsalite® after synthesis, the material exhibits different sorption capacity and hydrolytic stability. Calcined Upsalite® has a higher sorption capacity compared to as-synthesized, but crystallizes into nesquehonite when stored in a relative humidity of 100 % for several days. The need to stabilize the material arises and the use of two different aminosilanes as surface stabilizers has been evaluated. Two different deposition techniques from gas phase have been used, atomic layer deposition and vapor phase grafting, which are evaluated and compared.   The results of the functionalization show an increase in decomposition temperature by ~25 °C of the functionalized materials compared to non-functionalized. The initial water sorption capacity of the functionalized material increases by up to 80 %, when stored in a relative humidity of 100 % for 24 h and shows a stabilizing effect after five cycles of repeated exposure to high humidity. The long term stability seems to have decreased due to pore collapse, when the functionalized material is cycled 5 times for one week in a repeated relative humidity of 100 %. The stability of the material when exposed to two liquids of different pH was also evaluated and the functionalized material exhibits a slower increase of the pH in the buffer solution, implying a retardation of Upsalite® dissolution. The conclusion is that a functionalization of the material with aminosilane increases the initial sorption capacity and has a stabilizing effect.

Ovarian cancer is the fifth leading cause of cancer death among women in United States and has an alarming 1.4% (1 in 71) lifetime risk. The lack of overt symptoms and the absence of a reliable screening test to detect ovarian cancer result in over 70% of women being diagnosed after the disease has spread beyond the ovary resulting in a poor prognosis. A key characteristic of ovarian cancer is the ability of tumor cells to evade apoptosis, or programmed cell death contributing to the limitless replicative potential, which is a hallmark of all carcinogenesis. There is conclusive evidence that levels of bcl-2 are elevated in ovarian cancer patients' indication that this protein is an ovarian cancer biomarker. The overall goal of this thesis is to functionalize a substrate for specific, sensitive and cost-effective bcl-2 capture. This surface will ultimately be incorporated into an acoustic wave-based diagnostic device for worldwide point-of-care (POC) ovarian cancer detection. This research looks to assess the capture of this analyte protein on a series of bioconjugated surfaces. For the research to be diagnostically applicable, certain factors reveal themselves as more important than others. Since the surface-bound capture antibody must recognize the bcl-2 protein, it is vital to ensure upright orientation of this specific antibody with high affinity for the analyte. Furthermore once integrated with a nanosensor, the surface will sense a change in the mass on the surface, which requires that the surface is highly resistant to non-specific binding. Bioconjugation techniques were employed to initiate self-assembled monolayers (SAM) of silanes, immobilize antibodies (via amine-crosslinking or direct adsorption of protein A/G) and disperse polyethylene glycol (PEG) reagents to reduce non-specific binding on the glass substrates. 3-aminopropyltrimethoxysilane (3-APTMS) and chlorodimethyloctylsilane (ODMS) were deposited on the surface to create initial hydrophilic and hydrophobic properties on which molecular self-assembly could occur. Testing a variety of assemblies with and without the presence of silanes, amine-crosslinking and PEGylation reagents, the substrate displaying the highest efficacy of bcl-2 capture was revealed. These various surfaces were assessed through contact angle and a novel sandwich enzyme linked immunosorbent assay (ELISA) for sensitivity and specificity of bcl-2 standard capture. The consistently low background and facile assembly of the ODMS based substrate with direct adsorption of protein A/G and the PEGylation reagent, Pluronic, was deemed the best functionalized surface for non-specific recruitment of the bcl-2 protein. The substrate also consistently displayed low signal-to-noise ratio which was of extreme importance in this research to guarantee the prevention of false-positive results when detecting nascent carcinogenic behavior. Elucidation of this substrate assembly is the first step towards the long term objective of this thesis, which is to construct a cost-effective early ovarian cancer detection device which can be implemented at the point-of-care to those who need it the most. This is ultimately expected to dramatically improve health outcomes for females worldwide.

Au cours de ce travail nous avons étudié la réalisation de couches moléculaires d’accroche terminées amine. Sur l’oxyde de silicium l’aminopropyletriméthoxysilane (APTMS) a été déposé à partir d’une solution, et via une méthode originale par voie sèche qui nous a permis de mettre en évidence les temps caractéristiques de greffage et d’organisation de la couche d’APTMS. Sur l’or, les monocouches d’aminoéthanethiol (AET) et d’aminothiophénol (ATP) ont été réalisées à partir d’une solution. Nous avons ensuite étudié les aspects structuraux et cinétiques du greffage des fullerènes C60 sur de telles couches d’accroche, constituées de terminaisons amines soit sur toute la surface soit en des zones isolées (couches binaires). Les techniques de spectroscopie UV-Visible, IRTF, Raman, et XPS ont permis d’observer le greffage des C60 sur les couches aminées. La spectroscopie Raman en mode exalté (SERS) a mis en lumière que les molécules d’ATP étaient plus inclinées après le greffage à reflux des C60. Les analyses des diverses couches à l’échelle moléculaire ont été menées par microscopie à sondes locales (AFM, STM), et les mesures électriques réalisées sur or à l’aide de la pointe STM ont montré le caractère isolant de la couche d’accroche seule et un gap proche de celui du C60 après greffage des fullerènes. Elles ont également mis en évidence que le C60 était greffé sélectivement sur les zones terminées amines des couches d’accroche binaires. Enfin, une application potentielle des couches de C60 étant les mémoires moléculaires, les propriétés électriques des diverses couches réalisées ont été mesurées à l’aide de contacts électriques évaporés. / In this work we studied the preparation of sticking amine- terminated molecular layers. On silicon dioxide, 3-aminopropyltrimethoxysilane (APTMS) was de- posited from a solution, and using an original dry method that allowed us to determine time constants of APTMS layer grafting and organization. On gold surfaces, monolayers of aminoethanethiol (AET) and aminothiophenol (ATP) molecules were prepared from a solution. Then, we studied structural and kinetic aspects of ullerene C60 grafting on such sticking layers, terminated by amines either all over the surface or on isolated areas (binary layers). UV-visible, FTIR, Raman and XPS spectroscopy techniques enabled to observe that C60 was grafted on the amine-terminated layers. Exalted Raman spec- troscopy (SERS) revealed ATP molecules were more tilted after C60 grafting under reflux. Analyses of all the layers were made at a molecular level by local probe microscopy (AFM, STM), and electrical measurements performed on gold using the STM tip showed the in- sulating nature of the sticking layer whereas a gap close to that of C60 appeared after grafting of fullerenes. They also highlighted that C60 was selectively grafted on amine- terminated zones within binary sticking layers. At last, one of potential applications of C60 layers being molecular memory cells, electrical properties of the various studied layers were measured through evaporated electrical contact pads.

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