Artificial ‘bio-nose’ could identify odours

Researchers in the US have announced plans to create a portable, biologically based ‘bio-nose’ capable of identifying odours in the built environment.

The research is backed by a four-year, $2 million (£1.6 million) grant from the National Science Foundation.

Project leader Elisabeth Smela, a UMD professor of mechanical engineering at the University of Maryland, said: “If we had handheld devices that could recognise complex odours, a lot of things would be possible.

“There are applications in food, wine, perfumes, medical diagnostics, homeland security, agriculture, mould detection and more.”

Species including dogs, humans and insects have an extraordinary capacity for smell, allowing them to distinguish an extensive array of odours across different environments.

To take advantage of nature’s capacity for olfactory reception and scent recognition, the researchers are working on developing a sensor based on living cells.

However, in the past, using cells for this type of application has been challenging because mammalian cells need to be fed and held at body temperature to be kept alive, necessitating a more practical approach.

Smela said: “Think about the yeast that you keep dried at home.

“Wouldn’t it be nice if we had some cells that we could keep dry until we were ready to use them?”

The team’s collaborators at the National Agriculture and Food Research Organization (NARO) in Japan developed an insect-based cell line capable of just that.

The cells can be desiccated, or dried, and then re-animated by adding fluid at room temperature.

These cells don’t normally express olfactory receptors, so the NARO researchers added the genes into the cell line to allow them to sense odours.

Currently, the researchers are studying how the cell line responds when it is introduced to different liquids—one step of many on the way to developing a fully usable bio-nose device.

Future challenges include detection of airborne odorants and using machine learning to discover how a collection of cells reacts when exposed to various odours in order to identify the sources.

Smela said: “The addition of biological components to technology as well as the positive impact that an artificial nose could have on people’s lives makes this research particularly exciting.”

Image: oanna Avery/Maryland Engineering