Scientists at the University of Leicester are hoping that they can help tackle pollution by developing the world's smallest electronic nose.

The new fingernail-sized device is designed to sniff out chemicals such as those found in car exhausts and factory emissions.

Dr Tim Pearce, who is coordinating the project, says the new "nose-on-a-chip" will go further than existing electronic technology, which is widely used in food and cosmetic quality control.

He believes it "could have very important implications" for fields as diverse as landmine detection and medical diagnosis.

More realistic

"One of the problems with existing electronic nose instruments is that they're very large and another thing is that they have limited similarities with the biological nose," Dr Pearce told the BBC.

"So one of the main points of this project is to build in more realism for the way that biology solves the problem of detecting chemicals compared to how technology does that at the moment."

Scientists are aiming to combine the odour sensors and the signal processing components onto one silicon chip.

The chip - around a square centimetre in size - would run on very little power.

Although designed to work in the same way, the device will not look like a human nose.

Instead, it will look like any silicon chip as found in computers but "with an open window on the surface that will allow chemicals to transfer in and to be sensed by the system," explained Dr Pearce.

The project is being developed in conjunction with teams at Warwick and Edinburgh universities with funding from the Swindon based Engineering and Physical Sciences Research Council.