Jun 19, 2012
Single-molecule chemical analysis for DNA sequencing
Stuart Lindsay’s lab at Arizona State University, US, has been developing a technology to exploit electron tunnel junctions as analytical devices. Called “recognition tunneling”, the method relies on adaptor molecules to recognize and hold analyte molecules in a tunnel junction. The electronic signal is stochastic, so it had appeared that many repeated reads would be required to identify each type of molecule. Despite this limitation, the technology has been licensed by Roche for DNA sequencing.
A new paper in the journal Nanotechnology demonstrates how a multiparameter analysis of each spike in the signal train can be used to call all 5 bases (A, T, C, G and the epigentically modified 5-methyl-C) with >90% accuracy. Thus true single-molecule chemical analysis is now enabled by a simple tunnel-junction device.
The study shows some short reads of a DNA sequence, which are then used to analyse binding kinetics in a recognition tunneling junction.
Full details can be found in the journal Nanotechnology.
About the author
Stuart Lindsay is director of the Center for Single Molecule Biophysics at Arizona State University, and Edward and Nadine Carson Professor of Physics and Chemistry.