Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Brown Engineers Use DNA to Direct Nanowire Assembly and Growth

17.07.2006
A small but growing number of engineers are using nature’s engineer – DNA – to create nanomaterials that can be used in everything from medical devices to computer circuits. A team from Brown University and Boston College is the first to use DNA to direct construction and growth of complex nanowires. Their work appears in Nanotechnology.

A research team led by Brown University engineers has harnessed the coding power of DNA to create zinc oxide nanowires on top of carbon nanotube tips. The feat, detailed in the journal Nanotechnology, marks the first time that DNA has been used to direct the assembly and growth of complex nanowires.


“If you want to make something, turn to Mother Nature” Engineers in the lab of Jimmy Xu used DNA to grow zinc oxide nanowires like this one on the tips of carbon nanotubes. The zinc oxide wires created in the lab measured between 100 and 200 nanometers long. Image: The Xu Laboratory

The tiny new structures can create and detect light and, with mechanical pressure, generate electricity. The wires’ optical and electrical properties would allow for a range of applications, from medical diagnostics and security sensors to fiber optical networks and computer circuits.

“The use of DNA to assemble nanomaterials is one of the first steps toward using biological molecules as a manufacturing tool,” said Adam Lazareck, a graduate student in Brown’s Division of Engineering. “If you want to make something, turn to Mother Nature. From skin to sea shells, remarkable structures are engineered using DNA.”

Lazareck, who works in the laboratory Jimmy Xu, professor of engineering and physics, led the research. The work is an example of “bottom up” nanoengineering. Instead of molding or etching materials into smaller components, such as computer circuits, engineers are experimenting with ways to get biological molecules to do their own assembly work. Under the right chemical conditions, molecular design and machinery – such as light-sensing proteins or viral motors – can be used to create miniscule devices and materials.

In this work, the team of engineers and scientists took the “bottom-up” approach one step further by successfully harnessing DNA to provide instructions for this self-assembly. The new structures created in the Xu lab are the first example of DNA-directed self-assembly and synthesis in nanomaterials.

The Xu lab is the first in the world to make uniform arrays of carbon nanotubes. Lazareck and his collaborators at Brown and Boston College built on this platform to make their structures. They started with arrays of billions of carbon nanotubes of the same diameter and height evenly spaced on a base of aluminum oxide film. On the tips of the tubes, they introduced a tiny DNA snippet.

This synthetic snippet of DNA carries a sequence of 15 “letters” of genetic code. It was chosen because it attracts only one complement – another sequence made up of a different string of 15 “letters” of genetic code. This second sequence was coupled with a gold nanoparticle, which acted as a chemical delivery system of sorts, bringing the complementary sequences of DNA together. To make the wires, the team put the arrays in a furnace set at 600° C and added zinc arsenide. What grew: Zinc oxide wires measuring about 100-200 nanometers in length.

The team conducted control experiments – introducing gold nanoparticles into the array with no DNA attached or using nanotubes with no DNA at the tips in the nanotube array – and found that very few DNA sequences stuck. And no wires could be made. Lazareck said the key is DNA hybridization, the process of bringing single, complimentary strands of DNA together to reform the double helices that DNA is famous for.

“DNA provides an unparalleled instruction manual because it is so specific,” Lazareck said. “Strands of DNA only join together with their complements. So with this biological specificity, you get manufacturing precision. The functional materials that result have attractive properties that can be applied in many ways.”

“We’re seeing the beginning of the next generation of nanomaterials,” said Xu, senior author of the article. “Many labs are experimenting with self-assembly. And they are making beautiful, but simple, structures. What’s been missing is a way to convey information – the instruction code – to make complex materials.”

Graduate student Teng-Fang Kuo was part of the Brown team along with two former graduate students in the Xu lab – Bradford Taft at Boston College and Sylvain Cloutier at the University of Delaware. Shana Kelley, professor of chemistry at Boston College, contributed to the experiments.

The Air Force Office of Scientific Research, the Office of Naval Research, the Defense Advanced Research Projects Agency and the National Sciences and Engineering Council of Canada funded the research.

Wendy Lawton | EurekAlert!
Further information:
http://www.brown.edu

More articles from Life Sciences:

nachricht Symbiotic bacteria: from hitchhiker to beetle bodyguard
28.04.2017 | Johannes Gutenberg-Universität Mainz

nachricht Nose2Brain – Better Therapy for Multiple Sclerosis
28.04.2017 | Fraunhofer-Institut für Grenzflächen- und Bioverfahrenstechnik IGB

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Making lightweight construction suitable for series production

More and more automobile companies are focusing on body parts made of carbon fiber reinforced plastics (CFRP). However, manufacturing and repair costs must be further reduced in order to make CFRP more economical in use. Together with the Volkswagen AG and five other partners in the project HolQueSt 3D, the Laser Zentrum Hannover e.V. (LZH) has developed laser processes for the automatic trimming, drilling and repair of three-dimensional components.

Automated manufacturing processes are the basis for ultimately establishing the series production of CFRP components. In the project HolQueSt 3D, the LZH has...

Im Focus: Wonder material? Novel nanotube structure strengthens thin films for flexible electronics

Reflecting the structure of composites found in nature and the ancient world, researchers at the University of Illinois at Urbana-Champaign have synthesized thin carbon nanotube (CNT) textiles that exhibit both high electrical conductivity and a level of toughness that is about fifty times higher than copper films, currently used in electronics.

"The structural robustness of thin metal films has significant importance for the reliable operation of smart skin and flexible electronics including...

Im Focus: Deep inside Galaxy M87

The nearby, giant radio galaxy M87 hosts a supermassive black hole (BH) and is well-known for its bright jet dominating the spectrum over ten orders of magnitude in frequency. Due to its proximity, jet prominence, and the large black hole mass, M87 is the best laboratory for investigating the formation, acceleration, and collimation of relativistic jets. A research team led by Silke Britzen from the Max Planck Institute for Radio Astronomy in Bonn, Germany, has found strong indication for turbulent processes connecting the accretion disk and the jet of that galaxy providing insights into the longstanding problem of the origin of astrophysical jets.

Supermassive black holes form some of the most enigmatic phenomena in astrophysics. Their enormous energy output is supposed to be generated by the...

Im Focus: A Quantum Low Pass for Photons

Physicists in Garching observe novel quantum effect that limits the number of emitted photons.

The probability to find a certain number of photons inside a laser pulse usually corresponds to a classical distribution of independent events, the so-called...

Im Focus: Microprocessors based on a layer of just three atoms

Microprocessors based on atomically thin materials hold the promise of the evolution of traditional processors as well as new applications in the field of flexible electronics. Now, a TU Wien research team led by Thomas Müller has made a breakthrough in this field as part of an ongoing research project.

Two-dimensional materials, or 2D materials for short, are extremely versatile, although – or often more precisely because – they are made up of just one or a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Fighting drug resistant tuberculosis – InfectoGnostics meets MYCO-NET² partners in Peru

28.04.2017 | Event News

Expert meeting “Health Business Connect” will connect international medical technology companies

20.04.2017 | Event News

Wenn der Computer das Gehirn austrickst

18.04.2017 | Event News

 
Latest News

Wireless power can drive tiny electronic devices in the GI tract

28.04.2017 | Medical Engineering

Ice cave in Transylvania yields window into region's past

28.04.2017 | Earth Sciences

Nose2Brain – Better Therapy for Multiple Sclerosis

28.04.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>