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Résumé

Un échange vigoureux au travers des frontières de la biologie et de la physique se développe autour de nouvelles méthodes et outils, et autour de nouveaux phénomènes. Les objets d'étude au coeur de ce recouvrement multidisciplinaire sont très divers. De manière non exhaustive, il s'agit de nanoparticules, de cellules ou encore d'objets encore plus petits et élémentaires tels que les molécules. Aussi bien pour des applications dans le domaine de la microélectronique que pour l'étude de mécanismes biologiques fondamentaux, l'intégration des objets d'intérêt à l'échelle de l'objet unique est essentielle. Dans le cadre de cette thèse, l'objectif que nous nous sommes fixés est de développer un volet technologique qui permette l'assemblage d'objets micro- ou nanométriques uniques à des endroits bien définis d'une surface solide de façon simple, fiable, bas-coût et parallèle. Pour ce développement, nous nous sommes intéressés tout particulièrement aux nanoparticules d'Au de 100 nm de diamètre, aux bactéries, puis aux molécules d'ADN. Nous décrirons les stratégies développées reposant sur la lithographie douce puis leurs potentialités pour différentes applications dans les domaines de l'analyse médicale et de la détection.

Abstract

A vigorous trade across the borders of biological and physical sciences is developing around new methods and tools, and around new phenomena. The objects at the heart of this multidisciplinary overlapping are numerous. In a non exhaustive manner, the objects of study can be nanoparticles, cells, or even smaller and more elementary objects such as molecules. For applications in the field of microelectronics as for studies of fundamental biological mechanisms, the integration of these objects of interest at the single object scale is essential. In the frame of this Ph.D. thesis, the objective we pursued is the development of a technological tool-box allowing the assembly of micro- and nano-objects at pre-determined locations of a solid surface, in a simple, reliable, low-cost and parallel manner. For this development, we focused on gold nanoparticles 100 nm in diameter, bacterial cells and DNA molecules in particular. We will describe the strategies developed relying on soft-lithography and their potentialities for different applications in the fields of medical analysis and sensing.

Mots-Clés / Keywords

Lithographie douce; Assemblage capillaire; Cellules; Molécules d'ADN; Nanoparticules; biopatterning; Biodétection; Soft-lithography; Capillary assembly; Cells; DNA molecules; Nanoparticles; Biodetection;

Abstract

In this paper we present an alternative approach to transfer-print controlled arrays of sub-100 nm gold nanoparticles onto a substrate with high placement accuracy. First, the assembly of gold nanoparticles is achieved on a topologically nanopatterned polydimethylsiloxane stamp through a convective and capillary assembly technique. Second, the dry particles assembly is subsequently printed from the plate onto plane substrates by contact through a thin film of liquid. We demonstrate that microcontact printing can be performed with solvent mediation for a high precision transfer of sub-100 nm individual particles and we discuss the most appropriate solvent. The transferred particles preserve their organization and physical properties.

Mots-Clés / Keywords

Gold nanoparticles; Convective and capillary assembly; Soft lithography; Transfert-printing; Solvent;

Abstract

Commonly, one of the challenges in the development of todays nanodevices is the integration of nano-objects or molecules onto desired locations on a substrate. This integration comprises their accurate positioning, their alignment and the preservation of their functionality with respect to assembly processes. Required are novel engineering approaches to overcome this problem. Here, we prove how capillary assembly in combination with soft-lithography can be used to perform phage lambda DNA molecular combing to generate chips of isolated DNA strands for genetic analysis and diagnosis. The assembly of DNA molecules was achieved on a topologically micropatterned polydimethylsiloxane (PDMS) stamp inducing almost simultaneously the trapping and stretching of single molecules. The DNA molecules were then transfer printed onto a glass slide coated by vapour deposition of 3-aminopropyltrimethoxysilane (APTMS) molecules. In fact, this technique offers the possibility to tightly control the experimental parameters to direct the assembly process in a highly reproducible manner. We can easily create arrays or more complex networks of stretched DNA molecules with high yield, while preserving their functionality.

Mots-Clés / Keywords

DNA; Molecular combing; Convective and capillary assembly; Soft lithography; DNA chip;

Abstract

Here, we prove how capillary assembly in combination with soft lithography can be used to perform DNA (yeast genomic and phage lambda) molecular combing to generate highly ordered arrays of isolated and perfectly aligned DNA strands for genetic analysis and diagnosis.

Abstract

Highly ordered arrays of single living bacteria were obtained by selective adsorption of bacteria onto chemical patterns with micrometric resolution. The chemically engineered template surfaces were prepared with the combination of microcontact printing process and a simple incubation technique. This methodology can be used for fundamental studies of bacterium's inner mechanisms and sub-cellular organization as well as for interfacing living bacteria with artificial microsystems.

Mots-Clés / Keywords

Soft lithography; Self-assembly; Bacteria; Surface functionalization; Microsystems;

Abstract

Here, we prove how capillary assembly in combination with soft lithography can be used to perform DNA (yeast genomic and phage lambda) molecular combing to generate highly ordered arrays of isolated and perfectly aligned DNA strands for genetic analysis and diagnosis.