"When things are this small, they are fantastically sensitive," says Professor Al-Amin Dhirani. "Such a circuit could make possible a bio-sensor that is activated by the reaction of just one molecule." This has the potential for detecting important biological molecules including DNA, he notes.
Dhirani found that when the metal tip of an electrical source is placed near a lever coated in gold nanoparticles, electrons jump from the tip to the nanoparticles. This pulls the lever toward the tip. His finding allows researchers to detect the presence of a single electron in a circuit. Up until now, researchers could show only the overall electron flow in nanoparticles.
He adds that different nanoparticles could be combined to create custom-designed electronic materials with specific electronic properties. The study, which appears in the Dec. 15 issue of Physical Review B, was funded by the Canadian Foundation for Innovation, the Connaught Fund, the Natural Science and Engineering Research Council for Canada, the Ontario Innovation Trust and the Nortel Institute.
CONTACT: Professor Al-Amin Dhirani, Department of Chemistry, 416-946-5789, adhirani@chem.utoronto.ca or Nicolle Wahl, U of T public affairs, 416-978-6974, nicolle.wahl@utoronto.ca
Physical Review B