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A combination of butterfly wings, vibrating mechanical beams and lasers to help detect lung cancer?

It might sound like science fiction but Gino Putrino’s research project proved so compelling to an international television program – PhD TV – that it was one of 11 chosen from a global field of 200 to be converted into an animated video with animation by Jorge Cham, creator of PhD comics and the 2011 film Piled Higher and Deeper: the Movie.

UWA graduate engineer and now PhD student Gino, from the School of Electrical, Electronic and Computer Engineering , said it wasn’t until the last minute that he entered the competition where PhD students attempted to explain their thesis in an audio recording of under two minutes.

“I was preparing for a conference and had been up until midnight packing and printing out material. I didn’t have to leave for the airport until 4am and I didn’t want to go to sleep just for a few hours so I decided I’d fill in time by entering,” he said.

Gino’s project, “Building an Artificial Nose”, is part of his PhD thesis.

“The air we breathe is packed full of invisible chemicals that carry a huge amount of useful information,” he said.

“A sensitive enough artificial nose could decipher this information, making it possible to tell if someone has lung cancer simply by sniffing their breath. An artificial nose could also detect explosives in an airport, tell if vegetables in a supermarket are fresh and when wine is fermented to the perfect level.

“Micro-electro-mechanical sensors (MEMS) are a new class of device which are sensitive enough to do all these things.

“The way they work is this: you make a suspended mechanical beam, clamped at one end. You then coat it with a substance which sticks to the specific chemical you want to sense. If you hit this beam, it will start vibrating at a speed that is its natural frequency.

“If the chemicals you are trying to sense then stick to the beam, the speed will change and, if you are able to detect the change, you have an incredibly sensitive artificial nose.”

The thickness of the beams Gino uses is one-hundredth the width of a human hair and vibrates at more than 20,000 times a second.

And the butterfly? “The colours on the Green Hairstreak butterfly’s shimmering wings aren’t created by pigments but nano-structured shapes which bend light, creating an effect called diffraction,” he said.

“Different colours of light are bent in different directions. If nature can do it, then we can: by fabricating a nanostructure underneath our beam and aiming a laser at it. The amount of light that reaches the other side will depend on the height of the beam. The light helps us measure the vibrations, which are too small and fast to be otherwise visible, even under a microscope.”

Gino’s work on this project, which has three patents pending so far, is in collaboration with Winthrop Professor John Dell , Dean of the Faculty of Engineering, Computing and Mathematics; Winthrop Professor Lorenzo Faraone , Director of the Centre for Semiconductor Optoelectronics and Microsystems; Professor Adrian Keating in the School of Mechanical and Engineering; and Professor Mariusz Martyniuk in the School of Electrical, Electronic and Computer Engineering.

Published in UWA News , 15 October 2012