Prof. Loïc Auvray "Transport of macromolecules through nanopores. From protein unfolding to flow injection of DNA"

Our group and several others in the world are studying the transport of single macromolecules through short and narrow channels of nanometric size by using a simple electrical detection, based on the change of conductance induced by the presence of a macromolecule in a channel. I will present experiments done by using natural passive protein channels reconstituted in lipid bilayers or by using solid state nanopores  drilled in ultrathin (10-100 nm) Silicon Nitride membranes by Focused Ion Beam (FIB) or electron beam. We study in particular the conformation and the dynamics of partially unfolded proteins, varying the pore size and comparing different mutants differing by their folding properties. We have recently investigated the forced translocation of single DNA molecules across solid state nanopores by applying a controlled flow and by monitoring the DNA motion by an optical detection.