Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Armchair Science: DNA Strands That Select Nanotubes Are First Step to a Practical ‘Quantum Wire’


Wrapped up in their work: Molecular model shows a single-strand DNA molecule (yellow ribbon) coiled around an "armchair" carbon nanotube.
Credit: Roxbury, Jagota/NIST
Wrapped up in their work: Molecular model shows a single-strand DNA molecule (yellow ribbon) coiled around an "armchair" carbon nanotube.
Credit: Roxbury, Jagota/NIST

Abstract:
DNA, a molecule famous for storing the genetic blueprints for all living things, can do other things as well. In a new paper,* researchers at the National Institute of Standards and Technology (NIST) describe how tailored single strands of DNA can be used to purify the highly desired "armchair" form of carbon nanotubes. Armchair-form single wall carbon nanotubes are needed to make "quantum wires" for low-loss, long distance electricity transmission and wiring.

Armchair Science: DNA Strands That Select Nanotubes Are First Step to a Practical ‘Quantum Wire’

Gaithersburg, MD | Posted on August 3rd, 2011

Single-wall carbon nanotubes are usually about a nanometer in diameter, but they can be millions of nanometers in length. It's as if you took a one-atom-thick sheet of carbon atoms, arranged in a hexagonal pattern, and curled it into a cylinder, like rolling up a piece of chicken wire. If you've tried the latter, you know that there are many possibilities, depending on how carefully you match up the edges, from neat, perfectly matched rows of hexagons ringing the cylinder, to rows that wrap in spirals at various angles—"chiralities" in chemist-speak.

Chirality plays an important role in nanotube properties. Most behave like semiconductors, but a few are metals. One special chiral form—the so-called "armchair carbon nanotube"**—behaves like a pure metal and is the ideal quantum wire, according to NIST researcher Xiaomin Tu.
Armchair carbon nanotubes could revolutionize electric power systems, large and small, Tu says. Wires made from them are predicted to conduct electricity 10 times better than copper, with far less loss, at a sixth the weight. But researchers face two obstacles: producing totally pure starting samples of armchair nanotubes, and "cloning" them for mass production. The first challenge, as the authors note, has been "an elusive goal."

Separating one particular chirality of nanotube from all others starts with coating them to get them to disperse in solution, as, left to themselves, they'll clump together in a dark mass. A variety of materials have been used as dispersants, including polymers, proteins and DNA. The NIST trick is to select a DNA strand that has a particular affinity for the desired type of nanotube. In earlier work,*** team leader Ming Zheng and colleagues demonstrated DNA strands that could select for one of the semiconductor forms of carbon nanotubes, an easier target. In this new paper, the group describes how they methodically stepped through simple mutations of the semiconductor-friendly DNA to "evolve" a pattern that preferred the metallic armchair nanotubes instead.

"We believe that what happens is that, with the right nanotube, the DNA wraps helically around the tube," explains Constantine Khripin, "and the DNA nucleotide bases can connect with each other in a way similar to how they bond in double-stranded DNA." According to Zheng, "The DNA forms this tight barrel around the nanotube. I love this idea because it's kind of a lock and key. The armchair nanotube is a key that fits inside this DNA structure—you have this kind of molecular recognition."
Once the target nanotubes are enveloped with the DNA, standard chemistry techniques such as chromatography can be used to separate them from the mix with high efficiency.

"Now that we have these pure nanotube samples," says team member Angela Hight Walker, "we can probe the underlying physics of these materials to further understand their unique properties. As an example, some optical features once thought to be indicative of metallic carbon nanotubes are not present in these armchair samples."

* X. Tu, A.R. Hight Walker, C.Y. Khripin and M. Zheng. Evolution of DNA sequences towards recognition of metallic armchair carbon nanotubes. J. Am. Chem. Soc., Just Accepted Manuscript, Web publication: July 21, 2011.

** From the distinctive shape of the edge of the cylinder.

*** X. Tu, S. Manohar, A. Jagota and M. Zheng. DNA sequence motifs for structure-specific recognition and separation of carbon nanotubes. Nature, 460, 250-253, July 9, 2009.

####

About NIST
The National Institute of Standards and Technology (NIST) is an agency of the U.S. Department of Commerce.

For more information, please click here

Contacts:
Michael Baum
(301) 975-2763

Copyright © NIST

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

News and information

Electric-car battery materials could harm key soil bacteria February 11th, 2016

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Nanoparticle reduces targeted cancer drug's toxicity February 11th, 2016

Cima NanoTech Debuts Large Interactive Touch Screens with European Customers at ISE 2016: For the first time in Europe, Cima NanoTech’s wide range of high performance, projected capacitive touch modules are showcased February 11th, 2016

Laboratories

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Scientists take nanoparticle snapshots February 10th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Electric-car battery materials could harm key soil bacteria February 11th, 2016

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Scientists take nanoparticle snapshots February 10th, 2016

Chip Technology

Research reveals carbon films can give microchips energy storage capability: International team from Drexel University and Paul Sabatier University reveals versatility of carbon films February 11th, 2016

New thin film transistor may lead to flexible devices: Researchers engineer an electronics first, opening door to flexible electronics February 10th, 2016

SUNY Poly and GLOBALFOUNDRIES Announce New $500M R&D Program in Albany To Accelerate Next Generation Chip Technology: Arrival of Second Cutting Edge EUV Lithography Tool Launches New Patterning Center That Will Generate Over 100 New High Tech Jobs at SUNY Poly February 9th, 2016

Electron's 1-D metallic surface state observed: A step for the prediction of electronic properties of extremely-fine metal nanowires in next-generation semiconductors February 9th, 2016

Nanotubes/Buckyballs/Fullerenes

Superconductivity: Footballs with no resistance - Indications of light-induced lossless electricity transmission in fullerenes contribute to the search for superconducting materials for practical applications February 9th, 2016

The iron stepping stones to better wearable tech without semiconductors February 8th, 2016

Nano-coating makes coaxial cables lighter: Rice University scientists replace metal with carbon nanotubes for aerospace use January 28th, 2016

Scientists provide new guideline for synthesis of fullerene electron acceptors January 28th, 2016

Discoveries

Research reveals carbon films can give microchips energy storage capability: International team from Drexel University and Paul Sabatier University reveals versatility of carbon films February 11th, 2016

Canadian Scientists Develop Innovative Protein Test for Zika February 11th, 2016

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Announcements

Research reveals carbon films can give microchips energy storage capability: International team from Drexel University and Paul Sabatier University reveals versatility of carbon films February 11th, 2016

Creating a color printer that uses a colorless, non-toxic ink inspired by nature February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Nanoparticle reduces targeted cancer drug's toxicity February 11th, 2016

Nanobiotechnology

Canadian Scientists Develop Innovative Protein Test for Zika February 11th, 2016

SLAC X-ray laser turns crystal imperfections into better images of important biomolecules: New method could remove major obstacles to studying structures of complex biological machines February 11th, 2016

Nanoparticle reduces targeted cancer drug's toxicity February 11th, 2016

Chemical cages: New technique advances synthetic biology February 10th, 2016

Quantum nanoscience

Nanoscale cavity strongly links quantum particles: Single photons can quickly modify individual electrons embedded in a semiconductor chip and vice versa February 8th, 2016

The iron stepping stones to better wearable tech without semiconductors February 8th, 2016

Spin dynamics in an atomically thin semi-conductor February 1st, 2016

New record in nanoelectronics at ultralow temperatures January 28th, 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