Ithaca, NY—In another small step for mankind, nanobiotechnologists at Cornell University have assembled functional biomolecular motors with propellers measuring approximately 750×150 nm.
The primitive motors, made by a bacterium in Cornell's Nanofabrication Facility, comprise an engine and tiny nickel propellers, attached to 200-nm tall posts. The whole device is about 1/5 the size of a red blood cell.
During the experiment, the propellers rotated at a top speed of eight revolutions per second for up to 21/2 hours in the presence of adenosine triphospate (ATP—the fuel of all cellular life). "It's a chemical engine," says Carlo Montemango, associate professor of biological engineering at Cornell. "It takes the ATP and hydrolyzes it, converting the ATP into adenosine diphosphate and an extra phosphate molecule." The energy released from breaking the chemical bonds powers the motor, which in turn produces about 120 piconewtons per nanometer of torque.
The possible precursors of nano-sized medical aides, the devices may one day—scientists hope—be able to produce their own energy through photosynthesis and self assemble inside living cells to fight viruses and other diseases on their own turf.