iNAPO: an electrochemical molecule sensor based on a single ion conducting nanopore in polymer foil

Abstract

The principles of fabrication and working mechanism of a (bio)molecular sensor based on a single nanopore in a polymer foil are described. Polymer foils are through-irradiated with a single ion of a heavy element at a particle accelerator. The ion damage zone in the polymer is chemically etched into a conical nanopore. The nanopore wall is functionalized by an appropriate coupling chemistry with a biorecognition unit. In an electrochemical cell, the foil acts as separation membrane. The electrolyte current flowing through the nanopore is measured as a function of the applied potential. In the presence of specific analyte molecules, which bioconjugate with the biorecognition unit, these ionic currents are changed. Thus, a highly sensitive nanosensor is available. The preparation and working principle of the nanosensor is described. As an example, results on the sensing of the alkali metal lithium, the small biomolecule glucose, and a protein (lectine) and are shown.