Nanopores and nanochannels: fabrication and applications in analytical biochemistry and colloid science

In this thesis, a presentation of nanopores and nanochannels will be given with the emphasis on fabrication as well as applications. Nanopores and nanochannels are the basic building blocks of fluidic devices with dimensions in the nanometer range. The major applications of such nanofluidic devices are to study and carry out analysis of biological molecules such as DNA and proteins. Taking the advantage of having comparable dimensions as single biomolecules, new and outperforming devices based on nanofluidics could be constructed to study and analyze one molecule at a time. A motivation and brief literature overview on single molecule experiments and analysis will be given. To have an idea of the physical forces and transport mechanisms inside nanopores and nanochannels, selected models will be presented and discussed in the framework of this thesis. Despite the similar dimensions, the development of nanopores and nanochannels has been very different. The research and development of nanopore based devices accelerated after Meller et al. showed that DNA with different sequence could be distinguished (Meller, 2000). The investigators proposed that there was a possibility to sequence DNA using just one molecule. The drive to sequence DNA using nanopores also showed that they are very powerful single molecule probes. The thesis reports for the first time the interactions between synthetic nanopores and proteins. Another part of thesis, in the form of a manuscript under preparation, describes such interaction under different environmental conditions. To illustrate the capabilities of nanopore sensing, a protein-protein affinity assay which did not require any labeling was demonstrated. The nanopore fabrication process developed at IMT is included in the above paper and manuscript and critical steps are described in detail in the appendix. Unlike nanopores, the development efforts of nanochannels have been broader and acquired a more diversified application profile. An introduction is given in single molecule analytical biochemistry and the other promising application of nanofluidic devices - colloid science. Recent developments in nanofabricated devices present a new experimental platform for colloid science, which was previously unavailable. A part of the author’s work at IMT was a subject in colloid science; the filling of nanochannels by capillary force. The nanochannel fabrication process developed at IMT is also presented.

Thèse de doctorat : Université de Neuchâtel, 2006 ; 1908