Chemistry research team perform breakthrough studies

A research team led by Joshua Edel and Tim Albrecht, has recently performed breakthrough studies which could lead to a next generation platform for high throughput DNA sequencing.

 A research team led by Dr Joshua Edel and Dr Tim Albrecht, from the Department of Chemistry, has recently performed breakthrough studies which could lead to a next generation platform for high throughput DNA sequencing (" DNA sequencing-by-tunnelling").

The team has used nanofabrication techniques to develop a small chip device that is able to detect DNA molecules simultaneously by ion current and tunnelling current. The sensor consists of a nanopore to force DNA into a linear configuration and a tunneling junction aligned with the nanopore, to eventually read out the DNA sequence in real-time. Building such a device approaches the atomic scale and is effectively at the limit of current instrumentation. The central idea behind "DNA sequencing-by-tunnelling" is that the tunnelling junction provides both very high spatial resolution and electronic specificity. Provided that the individual DNA bases possess significantly different tunnelling conductance, the DNA sequence information could be read from the tunnelling current as DNA passses through the nanopore and the tunnelling junction. This approach would not require any labelling or DNA modification and is, at the same time, extremely rapid - all important pre-requisites for ultra-fast and cheap DNA sequencing in biomedical diagnostics or personalized medicine.

The Imperial team has now taken an important step towards this goal by integrating a tunnelling sensor with a solid-state nanopore. While sequencing as such has not been achieved yet, it could be shown that tunnelling detection of DNA in a high-throughput platform is possible. The full article was published in Nano Letters  on 6 December 2010 where it was the most downloaded paper in December. Further information can also be found on the College news website