Solar power is one of the most intense areas of research around the globe as scientists and researchers look for alternative power methods that will free society from fossil fuel dependence. As solar panels become more efficient, they can generate more power making them a viable alternative.

Typically, using power from light involves capturing and storing that energy in a battery or other device. However, a group of chemists from the University of Florida has developed a new nanoscale motor that is able to turn light directly into motion. The researchers point out that the discovery is on a "very, very, very small scale."

The nanomotor is not the first motor to be driven by particles of light; it is however, the first nanomotor built entirely from a single molecule of DNA. The simplicity of using a single DNA molecule reportedly makes the nanomotor easier to manufacture and develop. The researchers hope that one day the nanomotor may be used in areas ranging from medicine to manufacturing.

Huaizhi Kang, the first author of the paper reporting the findings said, "It is easy to assemble, has fewer parts and theoretically should be more efficient."

The nanomotor is exceptionally small. In its collapsed form, the nanomotor is only two to five nanometers. When in its uncollapsed form, the nanomotor is 10 to 12 nanometers long. The tiny nanomotor is able to convert considerably more of the energy in sunlight to power than traditional solar cells report the scientists.

However, the amount of momentum it can generate is directly proportional to its size. Applications outside of very small-scale uses are a long way off because of the small scale of the nanomotor. The researchers say it would take untold trillions of the nanomotors working conjunction to power a vehicle or other large device. Producing real power form the tiny nanomotors is the big challenge says the researchers.

"The major difficulty lies ahead," said Weihong Tan, a UF professor of chemistry and physiology, author of the paper and the leader of the research group reporting the findings. "That is how to collect the molecular level force into a coherent accumulated force that can do real work when the motor absorbs sunlight."

He continued saying, "Some prototype DNA nanostructures incorporating single photo-switchable motors are in the making which will synchronize molecular motions to accumulate forces."

To make the nanomotor, the researchers combined a DNA molecule created in the lab with azobenzene, a chemical compound that reacts to light. The researchers then attached fluorophore, a light emitter, to one end of the nanomotor and a quencher to douse the light to the other end. The researchers say preparation of the DNA is easy and very safe.

"Radiation does cause things to move from the spinning of radiometer wheels to the turning of sunflowers and other plants toward the sun," said Richard Zare, distinguished professor and chairman of chemistry at Stanford University. "What Professor Tan and co-workers have done is to create a clever light-actuated nanomotor involving a single DNA molecule. I believe it is the first of its type."