Track-etched nanopore applications research
at the Dept. of Electrical and Electronic Engineering
University College Cork, Ireland
Projects
Nanopore-based DNA analysis
Nanopore-based DNA analysis is a single-molecule DNA analysis technique, still at the research stage, which has the potential to operate orders of magnitude faster than today's methods.
The concept is surprisingly simple. As
shown below, an electrochemical system is used, where an applied
voltage drives a flow of ions through a nanopore. The DNA molecule
to be analysed is then driven through the pore, also by the applied
voltage, blocking the flow of ions as it does so. This ion flow can be
measured as a current flowing in the electrical circuit, and because the
pore is chosen to have a diameter sufficiently small that DNA is forced
to pass through as a linear strand, the molecule's properties—length,
and ultimately sequence—can be determined based on the duration of
current blockage, and variations in its magnitude.
This project is being carried out in collaboration with Birgitta Schiedt, Reinhard Neumann at the GSI Research Institute, Darmstadt, Germany (web), and Zuzanna Siwy at the Dept. of Physics and Astronomy, University of California, Irvine, USA (web).
more >
Commercialising nanopores: Automated production and robust packaging for track-etched single-nanopore membranes
Synthetic single-nanopore membranes (with pore diameters in the range 1–50 nm) have promising capabilities for nanoscale science and technology. However, although nanopore production techniques are well developed, they have not moved beyond the research level, i.e. they are low-volume, labour-intensive processes (e.g. for track-etched nanopores: 100's of pores per year, hours of labour per pore). Currently, there is no commercial production of single-pore membranes, and this low availability is likely a limiting factor on growth of the research field.
This project aims to demonstrate the commercial potential and feasibility of track-etched single-nanopore membranes.
Towards this goal, the potential market is under investigation,
systems are being constructed to automate the etching and testing processes,
and new more robust nanopore substrates are being developed with added features for easier use and more functionality.
Enterprise Ireland are funding this project under their Proof of Concept scheme.
Background
Track-etched nanopores are formed by chemically etching particle-tracks in materials. These tracks can be naturally occurring, for example due to fission fragments from the decay of naturally occurring radioactive elements in minerals, or they can be artificially produced, e.g. in a heavy ion accelerator.
Soon after it was observed that these tracks could be chemically etched, their potential was recognised for very-fine-pore filter membranes (P.B. Price and R.M. Walker, U.S. Patent 3303085, 1967). In the 1980's, R. Spohr and others at the Gesellschaft für Schwerionenforschung in Germany developed the single-ion irradiation system, capable of producing single tracks by detecting each individual ion after it has passed through the sample and then quickly diverting the ion beam.
A range of research is now based on these single-pore membranes. They are used as templates for the growth of nanowires, as tools for DNA analysis, as biosensors, and as model systems for the study of nanoscale ion transport phenomena.
Presentations, posters and articles
Ken Healy, Z. Siwy, A.P. Morrison and R. Neumann,
"Elastic and Plastic Deformation of Individual Conical Polymer Nanopores",
48th Biophysical Society Meeting, Baltimore, USA, February 2004.
PDF
Ken Healy, B. Schiedt, Z. Siwy, A.P. Morrison and R. Neumann,
"Single-molecule DNA Transport Through Individual Conical Polymer Nanopores",
49th Biophysical Society Meeting, Long Beach, USA, February 2005.
PDF
Birgitta Schiedt, K. Healy, A.P. Morrison, R. Neumann and Z. Siwy,
"Transport of ions and biomolecules through single asymmetric nanopores in polymer films",
Nucl. Instrum. Methods B, 236:109–116, 2005.
ScienceDirect link (subscription required to view full-text or PDF)
Ken Healy and A.P. Morrison,
"Plans for automated etching and user-friendly packaging for track-etched single-nanopores",
Summerschool on Biosensing with Channels, International University Bremen, Germany, August 2006.
PDF
Ken Healy and A.P. Morrison,
"An optical-feedback picoammeter for nanopore-based sensing",
Third Focused Workshop on Electronic Recognition of Bio-Molecules, Université de Liège, Belgium, September 2006.
PDF
Eric Kalman, K. Healy and Z. Siwy,
"Tuning of ion current rectification in asymmetric nanopores by signal mixing",
Europhys. Lett., 78:28002, 2007.
PDF | EPL Online link (subscription required to view full-text or PDF)
Ken Healy and A.P. Morrison,
"Recent progress in automated production and robust packaging for track-etched single-nanopores",
51st Biophysical Society Meeting, Baltimore, USA, March 2007.
PDF
Ken Healy,
"Nanopore-based single-molecule DNA analysis: A review",
Nanomedicine, 2:459–481, 2007.
PDF | Nanomedicine Online link (subscription required to view full-text or PDF)
Ken Healy, B.Schiedt and A. P. Morrison
"Solid state nanopore technologies for nanopore-based DNA analysis",
Nanomedicine, 2:875–897, 2007.
PDF | Nanomedicine Online link (subscription required to view full-text or PDF)
Mubarak Ali, B. Schiedt, K. Healy, R. Neumann and W. Ensinger, "Modifying the surface charge of single track-etched conical nanopores in polyimide", Nanotechnology, 19:85713, 2008.
Nanotechnology Online link (subscription required to view full-text or PDF)
updates
New article
M. Ali, B. Schiedt, K. Healy, R. Neumann and W. Ensinger, "Modifying the surface charge of single track-etched conical nanopores in polyimide", Nanotechnology, 19:85713, 2008.
Nanotechnology Online link
New article
K. Healy, B.Schiedt and A. P. Morrison, "Solid-state nanopore technologies for nanopore-based DNA analysis", Nanomedicine, 2:875–879, 2007.
PDF | Nanomedicine Online link
New article
K. Healy, "Nanopore-based single-molecule DNA analysis: A review", Nanomedicine, 2:459–481, 2007.
PDF | Nanomedicine Online link