Fighting pollution, nano-style
Ammonia is one of the smallest chemical molecules – so it’s fitting that a 20-gram gadget will be fighting ammonia air pollution in India. It also makes sense: ammonia is one of the most common Indian urban pollutants, but its size makes detection difficult, and it often accumulates in inaccessible places. “Thinking small” could be the answer.
As a leading expert in BioMEMS, an application of micro-nanotechnologies in biology, Concordia Research Chair Muthukumaran Packirisamy knows all about working in miniature. He has built a thumbnail-sized sensor that is on its way to India, where it will be attached to a micro air vehicle and flown into areas where ammonia pollution is suspected.
“Finding air pollutants, especially in big cities, is made easier with micro air vehicles equipped with sophisticated sensors like this,” says Packirisamy, holding up the device. “They can help in mapping the problem.”
Once in the sky, Packirisamy’s sensor admits air through inlets. If the incoming air carries ammonia, the sensing technology will not only detect it, but also measure its concentration. All this takes about 30 seconds, and perhaps the best part is that the sensor can wirelessly transmit results to a ground station, so data is available almost instantly.
The level of precision needed to fabricate and test such devices is enormous. Even the presence of dust can throw off the best-laid plans – which is why Packirisamy and his team make use of the faculty’s specially designed clean rooms.
This latest research is the result of a fruitful collaboration between Packirisamy’s Optical-Bio Microsystems Laboratory and partners in Bangalore, India: the National Design and Research Forum of the Institution of Engineers (India), Anna University’s Foundation for Educational Excellence and Jain University.
When the current project wraps up, Packirisamy would like to develop sensors that can detect other pollutants. Starting with ammonia means, in his words, “starting with the most difficult one.”
• Department of Mechanical and Industrial Engineering
• Faculty of Engineering and Computer Science
• Optical Bio-Microsystems Laboratory