Single DNA molecule used to create smallest diode in all the land

Researchers have created the world's smallest diode and they did it using a single molecule of DNA. The creation was devised by researchers from the University of Georgia and Ben-Gurion University in Israel. The creation has shown for the first time that nanoscale electronic components can be made using a single DNA molecule. The breakthrough is seen as an advance that could aid in the search for replacement in silicon chips.

"For 50 years, we have been able to place more and more computing power onto smaller and smaller chips, but we are now pushing the physical limits of silicon," said Bingqiun Xu, an associate professor in the UGA College of Engineering and an adjunct professor in chemistry and physics. "If silicon-based chips become much smaller, their performance will become unstable and unpredictable."

Xu believes that the predictability of DNA, diversity, and programmability make the substance a major candidate for use in the design of functional electronic devices using single molecules. Xu and his collaborators published a paper that describes a diode created using a single molecule of DNA. A diode is a component that is vital to the function of electronic devices as it allows current to flow in one direction while preventing flow in the other direction.

The diode was designed using a single duplex DNA of 11 base pairs that was connected to an electronic circuit a few nanometers in size. The team then site-specifically intercalated a small molecule of coralyne into the DNA. After placing that coralyne into the system, the current flowing through the DNA was 15 times stronger for negative voltages than for positive voltages, that difference is a required component for a diode.

"Our discovery can lead to progress in the design and construction of nanoscale electronic elements that are at least 1,000 times smaller than current components," Xu said.

SOURCE: EurekAlert