Bangalore: Indian scientists have come out with carbon nanotube flow sensors that generate electric current when placed in moving liquid, a finding that promises to have enormous applications in the bio-medical field.

The scientists based in Bangalore, India's technology capital, say the tiny sensors, made out of bundles of carbon nanotubes, can be used as energy conversion device.

"If you have a flowing environment and if you put the sensor, you get voltage/current out of it. If you put it in a biomedical environment, you can get voltage/current out of it that can be used for therapeutic purposes for the body itself", says Prof Ajay K Sood, a Professor of Physics at the Indian Institute of Science.

The sensors, which do not incorporate any moving parts and considered a possible advance for the lab on a chip, were built by Prof Sood along with N Kumar of the Raman Research Institute and IISc student Shankar Ghosh. The research team's paper was published by the reputed 'Science Express' last week.

Prof. Sood said on January 22 that the team has applied for patent in the US and India as they believed that "all the indications are that it (sensor) has immense potential".

"Whomsoever we have talked to, we have got that feeling. I think it's exciting," he said of the "physics-driven experiment".

Stating that the flow of a liquid on single-walled carbon nanotube (SWNT) bundles induces a voltage/current, Sood said the magnitude of the voltage/current depends sensitively on the ionic conductivity and the polar nature of the liquid.

According to him, the sensor can be scaled down to length dimensions - microns, the length of the individual nanotubes, making it usable in very small liquid volumes.

The sensor also has high sensitivity at low velocities, and a fast response time, he said, adding it can detect very small velocities.

PTI