Satellite Banner
qPCR
Scientific Community
 
Become a Member | Sign in
Home>News>This Article
  News
Return

Graphene Nanoribbons for “Reading” DNA

Published: Tuesday, November 19, 2013
Last Updated: Tuesday, November 19, 2013
Bookmark and Share
One of the methods used for examining the molecules in a liquid consists in passing the fluid through a nano-sized hole so as to detect their passage.

EPFL researchers have found a way to improve this technique by using a material with unique properties: graphene.

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.

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.

A thickness of one third of a nanometer
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.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,300+ scientific posters on ePosters
  • More than 4,900+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.


Scientific News
CDC Updates Zika Recommendations
CDC has issued updated Zika recommendations and guidance for healthcare providers with a focus on sexual transmission.
Lab-Tested Diagnosis Needed When Treating Persistent Diarrhea
New PCR multiplex method makes lab testing more effective.
Biomarker for Multiple Sclerosis Detection Discovered
Winthrop-University Hospital researchers discover biomarker for multiple sclerosis detection.
Scientists Link Bipolar Disorder to Unexpected Brain Region
Researchers from The Scripps Research Institute have found that gene within the brain’s striatum could be linked to biopolar disorder.
Quick, Early Test For Ebola Could Prevent Epidemics
Researchers from Princeton University are collaborating with U.S. government labs to develop a more rapid, accurate and inexpensive test for the Ebola virus with the aim of identifying infections before carriers become symptomatic and contagious.
From Super to Ultra-Resolution Microscopy
A new method pushes the frontier in imaging resolution, with the potential to distinguish individual features in single molecules.
Cancer Research UK joins forces with U.S. 'Cancer Moonshot'
Cancer Research UK and the US government’s National Cancer Institute have announced that two teams will work together to radically accelerate progress against cancer, in one of the first international collaborations inspired by US Vice President Joe Biden’s Cancer Moonshot.
Assessing the Effectiveness of Genome-Editing Technologies
Researchers have developed a cost-effective and rapid method for assessing edits generated by CRISPR-Cas9 and other genome-editing technologies.
Measuring the Abundance of Extremely Rare Mutations
Researchers from Rutgers University demonstrate the use of multiplex real-time PCR assays to measure the abundance of extremely rare mutations associated with cancer.
Harnessing Helpful Microbes
Seeking to further harness microbes’ many uses, the federal government has launched the National Microbiome Initiative (NMI) to “foster the integrated study of microbiomes across different ecosystems.”

SELECTBIO Market Reports
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,300+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
4,900+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!