Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Duke scientists ’program’ DNA molecules to self assemble into patterned nanostructures

26.09.2003


Duke University researchers have used self-assembling DNA molecules as molecular building blocks called "tiles" to construct protein-bearing scaffolds and metal wires at the billionths of a meter, or "nanoscale."



The achievements in nanoscale synthesis, which the five authors said could lead to programmable molecular scale sensors or electronic circuitry, were described in a paper in the Sept. 26, 2003, issue of the journal Science written by HaoYan, Thom LaBean, Gleb Finkelstein, Sung Ha Park and John Reif.

The Duke group’s research was funded by the National Science Foundation, the Defense Advanced Research Project Agency, and an industrial partners arrangement with Taiko Denki Co., Ltd. Fashioning protein nanoscaffolds and silver nanowires may be only the beginning, because tiles of this form "can be easily programmed by varying the sticky ends to form more sophisticated arrays," the authors wrote.


"Our goal is to use DNA self-assembly to precisely control the location of other molecules," said Yan, a molecular chemist working as an assistant research professor in Duke’s computer science department.

"The big promise is that if we can increase the size of our lattices we can template nanoelectronics onto them and make useful devices and circuits at a smaller scale than has ever been done before," added LaBean, a molecular biologist who is also an assistant research professor of computer science.

Yan and LaBean are the tiles’ principal designers. Their work in DNA computation shows that the tiles’ self assembly into structures can be programmed, according to the researchers. "The tile itself is easy to modify by changing strands, so we can program the tile again and again for other purposes," Yan said.

Because DNA strands naturally, but selectively, stick together, the Duke team reported in the Science paper that they could make the DNA strands arrange themselves into cross shaped "tiles" capable of forming molecular bonds on all four ends of the cross arms. As a result, large numbers of the crosses could naturally stick together to form semi-rigid waffle-patterned arrays that the authors called "stable and well behaved."

Since two types of DNA component units called bases selectively pair up with the two others to form DNA strands -- that is, adenine with thymine and guanine with cytosine -- the scientists could exploit those biochemical properties to program different ways for their tiles to link together.

When the tiles were programmed to link with their faces all oriented in the same up or down direction, they self-assembled into narrow and long waffled "nanoribbons." But when each tile’s face was programmed to point in the opposite direction from its neighbor, wider and broader waffled "nanogrids" were formed, the authors wrote.

In the case of the nanogrids, the authors found they could affix protein molecules to the cavities that the DNA tiles naturally formed at the center of each cross.

To affix the proteins, they first attached the chemical biotin to parts of the DNA strands they knew would self-assemble in the cavities. Then they added the protein streptavidin to the solution containing self assembled nanogrids. As a result, the biotin and streptavidin bound, in a reaction familiar to protein chemists. So complexes of protein molecules assembled atop those cavities.

"To use DNA self-assembly to template protein molecules or other molecules has been sought for years, and this is the first time it has been demonstrated so clearly," said Yan. LaBean added that biomedical researchers could use such molecule-bearing nanogrids to detect other molecules. "Single molecule detection is one of the holy grails for sensors and diagnostics," he said.

The researchers also used a two-step chemical procedure to coat silver onto the DNA nanoribbons to produce electrically-conducting nanowires. Assistant physics professor and nanoscientist Finkelstein, with graduate student Park, then deposited nanoscale metal connecting leads using a technique called electron beam lithography.

Building tiles of DNA arranged in angular shapes was pioneered in the laboratory of biochemist Nadrian "Ned" Seeman of New York University, where Yan earned his Ph.D. LaBean has collaborated for several years with Duke computer science professor Reif on designing DNA tiles for use as elements in biomolecular computation.

The idea of using the tiles as the equivalents of computing bits draws on the fact that DNA molecules stick together in predictable ways and can also, because of their nanoscale sizes, interact in extremely large numbers within small containers of solution.

Monte Basgall | EurekAlert!
Further information:
http://www.duke.edu/

More articles from Life Sciences:

nachricht The balancing act: An enzyme that links endocytosis to membrane recycling
07.12.2016 | National Centre for Biological Sciences

nachricht Transforming plant cells from generalists to specialists
07.12.2016 | Duke University

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Significantly more productivity in USP lasers

In recent years, lasers with ultrashort pulses (USP) down to the femtosecond range have become established on an industrial scale. They could advance some applications with the much-lauded “cold ablation” – if that meant they would then achieve more throughput. A new generation of process engineering that will address this issue in particular will be discussed at the “4th UKP Workshop – Ultrafast Laser Technology” in April 2017.

Even back in the 1990s, scientists were comparing materials processing with nanosecond, picosecond and femtosesecond pulses. The result was surprising:...

Im Focus: Shape matters when light meets atom

Mapping the interaction of a single atom with a single photon may inform design of quantum devices

Have you ever wondered how you see the world? Vision is about photons of light, which are packets of energy, interacting with the atoms or molecules in what...

Im Focus: Novel silicon etching technique crafts 3-D gradient refractive index micro-optics

A multi-institutional research collaboration has created a novel approach for fabricating three-dimensional micro-optics through the shape-defined formation of porous silicon (PSi), with broad impacts in integrated optoelectronics, imaging, and photovoltaics.

Working with colleagues at Stanford and The Dow Chemical Company, researchers at the University of Illinois at Urbana-Champaign fabricated 3-D birefringent...

Im Focus: Quantum Particles Form Droplets

In experiments with magnetic atoms conducted at extremely low temperatures, scientists have demonstrated a unique phase of matter: The atoms form a new type of quantum liquid or quantum droplet state. These so called quantum droplets may preserve their form in absence of external confinement because of quantum effects. The joint team of experimental physicists from Innsbruck and theoretical physicists from Hannover report on their findings in the journal Physical Review X.

“Our Quantum droplets are in the gas phase but they still drop like a rock,” explains experimental physicist Francesca Ferlaino when talking about the...

Im Focus: MADMAX: Max Planck Institute for Physics takes up axion research

The Max Planck Institute for Physics (MPP) is opening up a new research field. A workshop from November 21 - 22, 2016 will mark the start of activities for an innovative axion experiment. Axions are still only purely hypothetical particles. Their detection could solve two fundamental problems in particle physics: What dark matter consists of and why it has not yet been possible to directly observe a CP violation for the strong interaction.

The “MADMAX” project is the MPP’s commitment to axion research. Axions are so far only a theoretical prediction and are difficult to detect: on the one hand,...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

ICTM Conference 2017: Production technology for turbomachine manufacturing of the future

16.11.2016 | Event News

Innovation Day Laser Technology – Laser Additive Manufacturing

01.11.2016 | Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

 
Latest News

NTU scientists build new ultrasound device using 3-D printing technology

07.12.2016 | Health and Medicine

The balancing act: An enzyme that links endocytosis to membrane recycling

07.12.2016 | Life Sciences

How to turn white fat brown

07.12.2016 | Health and Medicine

VideoLinks
B2B-VideoLinks
More VideoLinks >>>