Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Tailored DNA shifts electrons into the 'fast lane'

21.06.2016

DNA nanowire improved by altering sequences

DNA molecules don't just code our genetic instructions. They can also conduct electricity and self-assemble into well-defined shapes, making them potential candidates for building low-cost nanoelectronic devices.


Each ribboning strand of DNA in our bodies is built from stacks of four molecular bases, shown here as blocks of yellow, green, blue and orange, whose sequence encodes detailed operating instructions for the cell. New research shows that tinkering with the order of these bases can also be used to tune the electrical conductivity of nanowires made from DNA.

Credit: Maggie Bartlett, NHGRI

A team of researchers from Duke University and Arizona State University has shown how specific DNA sequences can turn these spiral-shaped molecules into electron "highways," allowing electricity to more easily flow through the strand.

The results may provide a framework for engineering more stable, efficient and tunable DNA nanoscale devices, and for understanding how DNA conductivity might be used to identify gene damage. The study appears online June 20 in Nature Chemistry.

Scientists have long disagreed over exactly how electrons travel along strands of DNA, says David N. Beratan, professor of chemistry at Duke University and leader of the Duke team. Over longer distances, they believe electrons travel along DNA strands like particles, "hopping" from one molecular base or "unit" to the next. Over shorter distances, the electrons use their wave character, being shared or "smeared out" over multiple bases at once.

But recent experiments lead by Nongjian Tao, professor of electrical engineering at Arizona State University and co-author on the study, provided hints that this wave-like behavior could be extended to longer distances.

This result was intriguing, says Duke graduate student and study lead author Chaoren Liu, because electrons that travel in waves are essentially entering the "fast lane," moving with more efficiency than those that hop.

"In our studies, we first wanted to confirm that this wave-like behavior actually existed over these lengths," Liu said. "And second, we wanted to understand the mechanism so that we could make this wave-like behavior stronger or extend it to even longer distances."

DNA strands are built like chains, with each link comprising one of four molecular bases whose sequence codes the genetic instructions for our cells. Using computer simulations, Beratan's team found that manipulating these same sequences could tune the degree of electron sharing between bases, leading to wave-like behavior over longer or shorter distances. In particular, they found that alternating blocks of five guanine (G) bases on opposite DNA strands created the best construct for long-range wave-like electronic motions.

The team theorizes that creating these blocks of G bases causes them to all "lock" together so the wave-like behavior of the electrons is less likely to be disrupted by random wiggling in the DNA strand.

"We can think of the bases being effectively linked together so they all move as one," Liu said. "This helps the electron be shared within the blocks."

The Tao group confirmed these theoretical predictions using break junction experiments, tethering short DNA strands built from alternating blocks of three to eight guanine bases between two gold electrodes and measuring the amount of electrical charge flowing through the molecules.

The results shed light on a long-standing controversy over the exact nature of the electron transport in DNA, Beratan says. They might also provide insight into the design of tunable DNA nanoelectronics, and into the role of DNA electron transport in biological systems.

"This theoretical framework shows us that the exact sequence of the DNA helps dictate whether electrons might travel like particles, and when they might travel like waves," Beratan said. "You could say we are engineering the wave-like personality of the electron."

###

Other authors include Yuqi Zhang and Peng Zhang of Duke University and Limin Xiang and Yueqi Li of Arizona State University.

This research was supported by grants from the Office of Naval Research (N00014-11-1-0729) and the National Science Foundation (DMR-1413257).

CITATION: "Engineering nanometer-scale coherence in soft matter," Chaoren Liu, Yuqi Zhang, Peng Zhang, David N. Beratan, Limin Xiang, Yueqi Li, Nongjian Tao. Nature Chemistry, June 20, 2016. DOI: 10.1038/nchem.2545

Media Contact

Kara J. Manke
kara.manke@duke.edu
919-681-8064

 @DukeU

http://www.duke.edu 

Kara J. Manke | EurekAlert!

Further reports about: DNA DNA strands Electrons electricity genetic instructions sequences waves

More articles from Life Sciences:

nachricht Not of Divided Mind
19.01.2017 | Hertie-Institut für klinische Hirnforschung (HIH)

nachricht CRISPR meets single-cell sequencing in new screening method
19.01.2017 | CeMM Forschungszentrum für Molekulare Medizin der Österreichischen Akademie der Wissenschaften

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Traffic jam in empty space

New success for Konstanz physicists in studying the quantum vacuum

An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Sustainable Water use in Agriculture in Eastern Europe and Central Asia

19.01.2017 | Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

 
Latest News

New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland

19.01.2017 | Earth Sciences

Not of Divided Mind

19.01.2017 | Life Sciences

Molecule flash mob

19.01.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>