Résumé
Artificial nanopores are nanometer sized aperture made in synthetic thin films (polymer or inorganic). A single nanopore can be considered as a constitutive element from membranes. Recent advances in this field are bringing new tools for real time detection of target molecules at low concentration (fmol L-1). Biological channels inside the cell membrane are used as models to design solid-state nanopores. They allow ions or molecules transport through intra- and extra-cellular side, thanks to their high selectivity and their gating properties. Compared to their biological counterparts, limitations of the synthetic nanopores are their lack of selectivity and unresponsiveness towards external stimuli. However, the solid state presents several advantages compared to the biological ones, such as nanopores robustness, the control of the number of pores and a long lifetime (several days or weeks). Thus their surface functionalization would increase their selective transport properties, their abilities to detect biomolecules or to study more in details their fundamental mechanisms.In this thesis, we design first bi-functional nanopores, pH- and ligand-gated. To do it, we used biotin-avidin system grafted inside a polymeric nanopore. We demonstrated that it is possible to reversibly gate the nanopore with pH modulation. Moreover, we are able to detect protein labeled with biotin and antibodies by analyzing the current rectification. The major drawback comes from the irreversibility of its covalent bonds. By using a similar concept combined with polyelectrolytes, we obtain a reversible functionalization. Depending on the ligand, the ionic selectivity and the conduction properties can be modulated. Next, we focused on fundamental questions regarding polynucleotides translocation, and more precisely on the influence of the surface state of the nanopore (hydrophobicity, charge) when the Debye distance is similar to the pore diameter. We show that if the nanopore has the same charge as the polyAdenosine or polyCytosine, the translocation time decreases, and the energy barrier of entrance decreases compared to an uncharged hydrophobic nanopore. Then, by modifying the surface of the nanopore made in PET film, we are able to detect short single and double strand of DNA (10 to 40 bases). Finally, we tried to functionalize PET nanopores to avoid unspecific adsorption of proteins and to study the translocation of long fibrils of amyloids from lysozyme. This goal has not been entirely reach since we cannot claim that the fibrils translocate through the pore.In this thesis we show the interest and the need to functionalize the nanopores, to obtain biomimetic stimuli-responsive (pH and ligand), to avoid unspecific adsorption or to study transport properties with the nanopore. It is easy to upscale those techniques to multipores membranes. Thus it is possible to design membranes to enhance their ionic separation, target molecule detection or more generally filtration applications.