DNA could be backbone of next generation logic chips

May 11, 2010
These are many waffles. Credit: Chris Dwyer

(PhysOrg.com) -- In a single day, a solitary grad student at a lab bench can produce more simple logic circuits than the world's entire output of silicon chips in a month.

So says a Duke University engineer, who believes that the next generation of these at the heart of computers will be produced inexpensively in almost limitless quantities. The secret is that instead of silicon chips serving as the platform for electric circuits, computer engineers will take advantage of the unique properties of , that carrier of all life's information.

In his latest set of experiments, Chris Dwyer, assistant professor of electrical and computer engineering at Duke's Pratt School of Engineering, demonstrated that by simply mixing customized snippets of DNA and other molecules, he could create literally billions of identical, tiny, waffle-looking structures.

Dwyer has shown that these nanostructures will efficiently self-assemble, and when different light-sensitive molecules are added to the mixture, the waffles exhibit unique and "programmable" properties that can be readily tapped. Using light to excite these molecules, known as , he can create simple , or switches.

These nanostructures can then be used as the building blocks for a variety of applications, ranging from the biomedical to the computational.

"When light is shined on the chromophores, they absorb it, exciting the electrons," Dwyer said. "The energy released passes to a different type of chromophore nearby that absorbs the energy and then emits light of a different wavelength. That difference means this output light can be easily differentiated from the input light, using a detector."

Instead of conventional circuits using electrical current to rapidly switch between zeros or ones, or to yes and no, light can be used to stimulate similar responses from the DNA-based switches - and much faster.

"This is the first demonstration of such an active and rapid processing and sensing capacity at the molecular level," Dwyer said. The results of his experiments were published online in the journal Small. "Conventional technology has reached its physical limits. The ability to cheaply produce virtually unlimited supplies of these tiny circuits seems to me to be the next logical step."

This is a closeup of a waffle. Credit: Chris Dwyer

DNA is a well-understood molecule made up of pairs of complimentary nucleotide bases that have an affinity for each other. Customized snippets of DNA can cheaply be synthesized by putting the pairs in any order. In their experiments, the researchers took advantage of DNA's natural ability to latch onto corresponding and specific areas of other DNA snippets.

Dwyer used a jigsaw puzzle analogy to describe the process of what happens when all the waffle ingredients are mixed together in a container.

"It's like taking pieces of a puzzle, throwing them in a box and as you shake the box, the pieces gradually find their neighbors to form the puzzle," he said. "What we did was to take billions of these puzzle pieces, throwing them together, to form billions of copies of the same puzzle."

In the current experiments, the waffle puzzle had 16 pieces, with the chromophores located atop the waffle's ridges. More complex circuits can be created by building structures composed of many of these small components, or by building larger waffles. The possibilities are limitless, Dwyer said.

In addition to their use in computing, Dwyer said that since these nanostructures are basically sensors, many biomedical applications are possible. Tiny could be built that could respond to different proteins that are markers for disease in a single drop of blood.

Explore further: Introducing the multi-tasking nanoparticle

Related Stories

Physicists create first robust DNA building blocks

Dec 09, 2005

Physicists from the University of Oxford have designed the first structurally robust, self-assembling DNA building blocks. The DNA tetrahedra, 10,000,000,000 (ten thousand million) of which could fit on the ...

Molecular machines drive plasmonic nanoswitches

Feb 11, 2009

Plasmonics -- a possible replacement for current computing approaches -- may pave the way for the next generation of computers that operate faster and store more information than electronically-based systems and are smaller ...

Molecules could create tiny circuits on computer chips

Mar 16, 2010

(PhysOrg.com) -- As the features on computer chips become increasingly smaller, finding ways to fabricate the chips has become a big challenge. In a new study, researchers from MIT have demonstrated that certain ...

Recommended for you

Introducing the multi-tasking nanoparticle

15 hours ago

Kit Lam and colleagues from UC Davis and other institutions have created dynamic nanoparticles (NPs) that could provide an arsenal of applications to diagnose and treat cancer. Built on an easy-to-make polymer, these particles ...

Tissue regeneration using anti-inflammatory nanomolecules

Aug 22, 2014

Anyone who has suffered an injury can probably remember the after-effects, including pain, swelling or redness. These are signs that the body is fighting back against the injury. When tissue in the body is damaged, biological ...

Cut flowers last longer with silver nanotechnology

Aug 21, 2014

Once cut and dunked in a vase of water, flowers are susceptible to bacterial growth that shortens the length of time one has to enjoy the blooms. A few silver nanoparticles sprinkled into the water, might be the answer to ...

Relaxing DNA strands by using nano-channels

Aug 20, 2014

A simple and effective way of unravelling the often tangled mass of DNA is to 'thread' the strand into a nano-channel. A study carried out with the participation of the International School for Advanced Studies ...

User comments : 2

Adjust slider to filter visible comments by rank

Display comments: newest first

Alizee
May 11, 2010
This comment has been removed by a moderator.
Sciencebee
5 / 5 (2) May 11, 2010
I know this probably deserves a '1' rating but that picture made me think "Hey, that's my Rice Chex cereal in nano form!" Ah well, it's important to laugh in life :-)
random
5 / 5 (1) May 12, 2010
I love the caption: "These are many waffles." How vague can you get?