Carbon Nanotubes help to speed up Genetic Sequencing

The most optimum mannerism to customize treatment based on the genomic makeup of an individual and to personalize various diagnoses is through the faster sequencing of DNA. This would aptly benefit the medicinal and biological sectors. However today, such faster sequencing remains a very cumbersome process and is not being used in many clinics mainly on account of the large costs that are associated with it, although this might change due to the many different ground-breaking novel techniques.

At the Biodesign institute, the director of Arizona State University's Center for Single Molecule Biophysics, Stuart Lindsay along with his team of experts made use of a single-stranded ribbon of DNA to show the potential of such a method. This DNA ribbon was then used to produce spikes in voltage by threading it through a carbon nanotube. The information regarding the passing of the DNA bases through the tube, known as translocation was then recorded.

These carbon nanotubes used in optics, electronics, nanotechnology, and other scientific fields are cylindrical, versatile structures. Very often, they are made up of carbon allotropes that contain different carbon atoms assemblies, each displaying varying degrees of electrical conductivity and strength.

Most of the commonly used techniques for the reading of the genetic script, required the shredding of the DNA molecule into a thousand pieces after which, each of these sections would be read and then finally reconstructed into a complete genetic sequence by using the power of computers. Approximately 10 years ago, 3 billion chemical base pairs were decoded in what was the first human genome. Although this technique cost $1 billion dollars, it resulted in many errors as per the fragments that were read.

It was then that a newer strategy involving the use of nanopores was implemented. Here, at either end of the nanopores were electrodes that were charged with constant voltage thereby inducing ionic current throughout the nanopore's enclosed channel length. Through this channel, even a single molecule would be able to create a change in the ionic flow. After being electronically amplified, the current is then measured. Recently, many state of the art micro-manufacturing techniques have allowed various researchers to create small nanopores thus allowing many newer types of possibilities in the wake of single-molecule manipulations.

Lindsay and his team carried out a variety of different molecular simulations to find out the reasons for the large ionic currents in the nanotubes. The main hope is that by speeding up the process of genetic reading, it can become possible to identify DNA bases by their electrical current traces.