Nanotechnology Now

Our NanoNews Digest Sponsors


Heifer International

Wikipedia Affiliate Button

Home > Press > Graphene nanoribbons for 'reading' DNA: EPFL researchers improve the nanopore-based technology for detecting DNA molecules

Many efforts over last decade have been directed towards development of single molecule sequencing based on solid state nanopores. Aleksandra Radenovic and co-workers have made a device composed of a graphene nanoribbon transistor built on top of a solid state nanopore. Direct electrical readout from the graphene transistors is used to detect DNA translocation events. Nanopore, DNA and the graphene nanoribbon are shown in this schematic (which is not to scale).

Credit: EPFL
Many efforts over last decade have been directed towards development of single molecule sequencing based on solid state nanopores. Aleksandra Radenovic and co-workers have made a device composed of a graphene nanoribbon transistor built on top of a solid state nanopore. Direct electrical readout from the graphene transistors is used to detect DNA translocation events. Nanopore, DNA and the graphene nanoribbon are shown in this schematic (which is not to scale).

Credit: EPFL

Abstract:
If we wanted to count the number of people in a crowd, we could make on the fly estimates, very likely to be imprecise, or we could ask each person to pass through a turnstile. The latter resembles the model that EPFL researchers have used for creating a "DNA reader" that is able to detect the passage of individual DNA molecules through a tiny hole: a nanopore with integrated graphene transistor.

Graphene nanoribbons for 'reading' DNA: EPFL researchers improve the nanopore-based technology for detecting DNA molecules

Lausanne, Switzerland | Posted on November 18th, 2013

The DNA molecules are diluted in a solution containing ions and are driven by an electric field through a membrane with a nanopore. When the molecule goes through the orifice, it provokes a slight perturbation to the field, detectable not only by the modulations in ionic current but also by concomitant modulation in the graphene transistor current. Based on this information, it is possible to determine whether a DNA molecule has passed through the membrane or not.

This system is based on a method that has been known for over a dozen years. The original technique was not as reliable since it presented a number of shortcomings such as clogging pores and lack of precision, among others. "We thought that we would be able to solve these problems by creating a membrane as thin as possible while maintaining the orifice's strength", said Aleksandra Radenovic from the Laboratory of Nanoscale Biology at EPFL. Together with Floriano Traversi, postdoctoral student, and colleagues from the Laboratory of Nanoscale Electronics and Structures, she came across the material that turned out to be both the strongest and most resilient: graphene, which consists of a single layer of carbon molecules. The strips of graphene or nanoribbons used in the experiment were produced at EPFL, thanks to the work carried out at the Center for Micro Nanotechnology (CMI) and the Center for Electron Microscopy (CIME).

"Through an amazing coincidence, continued the researcher, the graphene layer's thickness measures 0.335 nm, which exactly fits the gap existing between two DNA bases, whereas in the materials used so far there was a 15 nm thickness." As a result, while previously it was not possible to individually analyze the passage of DNA bases through these "long" tunnels - at a molecular scale -, the new method is likely to provide a much higher precision. Eventually, it could be used for DNA sequencing.

However they are not there yet. In only 5 milliseconds, up to 50'000 DNA bases can pass through the pores. The electric output signal is not clear enough for "reading" the live sequence of the DNA strand passage. "However, the possibility of detecting the passage of DNA with graphene nanoribbons is a breakthrough as well as a significant opportunity", said Aleksandra Radenovic. She noted that, for example, the device is also able to detect the passage of other kinds of proteins and provide information on their size and/or shape.

This crucial step towards new methods of molecular analysis has received an ERC grant and is featured in an article published today in Nature Nanotechnology.

####

For more information, please click here

Contacts:
Aleksandra Radenovic

41-216-937-371

Copyright © Ecole Polytechnique Fédérale de Lausanne

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Graphene/ Graphite

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Graphene photodetectors: Thinking outside the 2-D box July 21st, 2016

A glimpse inside the atom: Using electron microscopes, it is possible to image individual atoms July 20th, 2016

News and information

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

XEI Scientific Partners with Electron Microscopy Sciences to Promote and Sell its Products in North and South America July 25th, 2016

Laboratories

An accelerated pipeline to open materials research: ORNL workflow system unites imaging, algorithms, and HPC to advance materials discovery and design July 24th, 2016

Scientists develop way to upsize nanostructures into light, flexible 3-D printed materials: Virginia Tech, Livermore National Lab researchers develop hierarchical 3-D printed metallic materials July 20th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 2016

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

Nanomedicine

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

New remote-controlled microrobots for medical operations July 23rd, 2016

New superconducting coil improves MRI performance: UH-led research offers higher resolution, shorter scan time July 23rd, 2016

New probe developed for improved high resolution measurement of brain temperature: Improved accuracy could allow researchers to measure brain temperature in times of trauma when small deviations in temperature can lead to additional brain injury July 23rd, 2016

Discoveries

Attosecond physics: Mapping electromagnetic waveforms July 25th, 2016

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

Announcements

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

XEI Scientific Partners with Electron Microscopy Sciences to Promote and Sell its Products in North and South America July 25th, 2016

Interviews/Book Reviews/Essays/Reports/Podcasts/Journals/White papers

Ultra-flat circuits will have unique properties: Rice University lab studies 2-D hybrids to see how they differ from common electronics July 25th, 2016

Borrowing from pastry chefs, engineers create nanolayered composites: Method to stack hundreds of nanoscale layers could open new vistas in materials science July 25th, 2016

Integration of novel materials with silicon chips makes new 'smart' devices possible July 25th, 2016

Accurate design of large icosahedral protein nanocages pushes bioengineering boundaries: Scientists used computational methods to build ten large, two-component, co-assembling icosahedral protein complexes the size of small virus coats July 25th, 2016

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







Car Brands
Buy website traffic