Whitney Palmer

Tiny DNA circuits offer high speed

Published in the July 19, 2010, Raleigh News & Observer and the July 19, 2010, Charlotte Observer

BY WHITNEY L.J. HOWELL – CORRESPONDENT

Imagine a cell phone that connects a call, or a computer that sends an e-mail at the speed of light. Work conducted by a Duke University engineer could usher in this new wave of electronic prowess.

Currently, silicon-based circuits power electronic devices. But there is a limit to how fast they can work and how small they can be. Using circuits made of DNA bypasses both problems, said Chris Dwyer, a researcher in Duke’s electrical and computer engineering department.

“DNA gives us the tools to make these information circuits as small as a protein,” Dwyer said. “Because DNA self-assembles, these circuits are faster to create, and they have an incredible capacity for sensing and processing.”

Mixing tailored segments of DNA together produces waffle-like structures that function as scaffolding for other sensors. Adding light-sensitive molecules, called chromophores, ignites the waffle structures’ programmable properties, turning them into switches with a wide array of applications other than electronic capabilities, including biomedical and computational capacities.

The waffle structure can be custom-made to detect different molecules in saliva, blood or urine. These structures

This waffle-like structure, made of DNA, can be made as small as a protein, says Duke University researcher Chris Dwyer. Photo courtesy of Duke University.

could be used with a cheek swab, Dwyer said, and a health practitioner could get same-day lab results for a battery of tests that it currently takes a week to complete.

The waffles also can be used as unique, sophisticated electronic encryption devices, he said.

The potential for these DNA-based circuits is substantial, said Jay Narayan, chairman of materials science in N.C. State University’s department of materials science and engineering. Making them work well for long stretches of time could be the hard part.

“Making this practical will be a challenge because DNA exists, by nature, in a solution, and electronic processes must have a solid surface to work,” he said. “We must also be careful because DNA is alive, and it can’t sustain the high temperatures that silicon-based structures endure to allow electronic devices to work.”

Narayan also said extending the DNA’s lifetime would be necessary to make it a plausible choice for electronic or clinical use.

For the Raleigh News & Observer article: http://www.newsobserver.com/2010/07/19/587472/tiny-dna-circuits-offer-high-speed.html

For the Charlotte Observer article: http://www.charlotteobserver.com/2010/07/19/1570543/tiny-dna-circuits-offer-high-speed.html

July 19, 2010 Posted by wjpalmer | Science | Chris Dwyer, DNA, DNA logic circuits, Duke University Pratt School of Engineering, Jay Narayan, North Carolina State University College of Engineering, proteins, tailored DNA | Leave a comment