Physical Society Colloquium

Democratizing Nanopore-based Single-Molecule Research

Vincent Tabard-Cossa

Department of Physics
University of Ottawa

In the last decade, driven by the promise of low-cost, rapid DNA sequencing, nanopores (i.e. holes of nanometer dimensions in a thin insulating membrane) have emerged as a unique class of single-molecule detectors, directly translating properties of biomolecules and their activities into an electrical signal.

The nanopore field was initially shaped by the ability of researchers to exploit biological channels to translocate individual molecules [Kasianowicz et al. (1996) PNAS]. Some years later, the field experienced a revolution when new techniques to fabricate nanometer scale holes in solid-state materials were developed [Li et al. (2001) Nature; Storm et al. (2003) Nature Materials]. These techniques, based on a beam of energetic ions or electrons allowed some well-equipped academic laboratories to sculpt a single nanopore in a thin, mechanically robust membrane, and tune its geometry, thus diversifying the breadth of applications. Since then, no other viable approaches for fabricating solid-state nanopores at the sub-10-nm length scale have emerged. However, one of today's greatest barriers to further development of the nanopore field is the complexity, low-throughput, and high-cost associated with these nanofabrication techniques. These factors restrict accessibility to the field to many researchers, greatly limit the productivity of the community, and prevent manufacturing of solid-state nanopore-based biotechnologies.

In this talk, I will present the development of an original nanofabrication strategy for making solid-state nanopores based on controlling breakdown of a dielectric membrane directly in solution [1, 2]. Dimensional control down to ~1-nm with sub-nm precision is achieved simply by applying a voltage across a membrane to generate a high electric field (>10⁸ V/m), and monitoring the induced tunneling current. This method effectively replaces ~million$ nanofabrication tools by a handheld battery-operated circuit, opening up a path to mass produce nanopore-based technologies, while also offering researchers new strategies for fabricating nanofluidic devices.

[1] Kwok et al. PLoS ONE 9(3):e92880(2014)
[2] Briggs et al. Small 10:2077-2086 (2014)