Researchers in Belgium are developing a sensitive 'electronic nose' that can detect pesticides and nerve gas in very low concentrations, using substances they call ''microscopic sponges.'' Matthew Stock reports.
STORY: A dog's nose can pick up minute odours undetectable to humans. They can be trained to sniff out explosives, drugs and - as with the labradors seen here - the scents that indicate certain diseases. But what if the power of your pooch's nose could be integrated into your smart phone? (SOUNDBITE) (English) ROB AMELOOT, ASSISTANT PROFESSOR AT UNIVERSITY OF LEUVEN, SAYING: "What this would be is basically an electronic nose. And if you can integrate it in a small, robust format that's cheap enough you could have it in your smart phone to detect air quality to early diagnosis of early types of diseases." This powder contains billions of microscopic structures called metal-organic frameworks, or MOFs It absorbs the molecules of a gas to trigger a reaction, such as changing colour. The team at this lab in Belgium are designing MOFs to 'soak up' specific gases. (SOUNDBITE) (English) ROB AMELOOT, ASSISTANT PROFESSOR AT UNIVERSITY OF LEUVEN, SAYING: "The materials we're working with are what's called molecular sponges, and they look like this [PICKS UP MODEL]. This is one hole of a molecular sponge. The diameter of this is about one nano-metre, that's one-hundred-thousand times smaller than the diameter of a human hair, and that's about the size of a molecule. So what we're trying to do is tailor the pores of these materials so the molecule fits in there." SOUNDBITE) (English) IVO STASSEN, POST-DOCTORAL RESEARCHER AT UNIVERSITY OF LEUVEN, SAYING: "At the first step we optimise the chemical synthesis of these materials and then we end up with a powder with the characteristics that we need. The next step, the next challenge will be, integrating these materials on solid devices." So far, they've created MOFs that absorb phosphonates, found in pesticides and nerve gases. They believe it's the most sensitive sensor yet made for these dangerous gases. Depositing a thin film of this powder onto an electronic circuit is the next step. They're hoping to have a solid state prototype ready within a year.