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 Scientists uncover the role of a protein in production & survival of myelin-forming cells
19.07.2018 | Advanced Science Research Center, GC/CUNY

nachricht NYSCF researchers develop novel bioengineering technique for personalized bone grafts
18.07.2018 | New York Stem Cell Foundation

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Future electronic components to be printed like newspapers

A new manufacturing technique uses a process similar to newspaper printing to form smoother and more flexible metals for making ultrafast electronic devices.

The low-cost process, developed by Purdue University researchers, combines tools already used in industry for manufacturing metals on a large scale, but uses...

Im Focus: First evidence on the source of extragalactic particles

For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.

To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...

Im Focus: Magnetic vortices: Two independent magnetic skyrmion phases discovered in a single material

For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.

Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...

Im Focus: Breaking the bond: To take part or not?

Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.

A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...

Im Focus: New 2D Spectroscopy Methods

Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.

"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Leading experts in Diabetes, Metabolism and Biomedical Engineering discuss Precision Medicine

13.07.2018 | Event News

Conference on Laser Polishing – LaP: Fine Tuning for Surfaces

12.07.2018 | Event News

11th European Wood-based Panel Symposium 2018: Meeting point for the wood-based materials industry

03.07.2018 | Event News

 
Latest News

A smart safe rechargeable zinc ion battery based on sol-gel transition electrolytes

20.07.2018 | Power and Electrical Engineering

Reversing cause and effect is no trouble for quantum computers

20.07.2018 | Information Technology

Princeton-UPenn research team finds physics treasure hidden in a wallpaper pattern

20.07.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>