It’s the next step in the evolution of cell-phone technology: a potentially life-prolonging microchip, compatible with any mobile phone, that alerts users to the presence of harmful chemicals in the air around them.

As part of a Department of Homeland Security project called “Cell-All,” the chip is being developed by a UCSD research group led by chemistry professor Michael Sailor, in conjunction with optics company Rhevision Technology. According to DHS Director Stephen Dennis, the program aims to turn an average cell phone into a portable chemical-detection device.

The chip samples the surrounding air for dangerous chemical compounds such as carbon dioxide, formaldehyde and propane.

“We had a breakthrough about a year ago to make these [sensors] specific to chemicals,” Sailor said. “Putting sensors on people is protecting the public health.”

Sailor said the technology was inspired by beetle shells, whose iridescent layers mimic the layers of silicon covered in light reflectors that make up the chips.

When airborne chemical molecules come into contact with the chip, the molecules bind and interfere with the light reflectors. Certain reflection patterns set off sensors that will then identify the compound.

Rhevision is supplying Sailor’s research team with an optical lens that monitors the nanosensors in the chip. When a sensor goes off, the lens detects which exact sensor it was, so the user will know which particular chemical is present in the surrounding air.

“When the chip detects a compound, the color changes to alert the user,” Sailor said.

At first detection, the chip will alert the owner to the presence and type of chemical via text message or cellular call. DHS plans to build a centralized emergency monitoring facility which will receive air sample analysis and location data from each remote chip when dangerous chemicals are detected. (For privacy reasons, users will be able to opt out of being tracked by the facility.)

Dennis said he hopes that up to 80 prototypes of the chip — which he predicted will cost $1 each — will be developed by the end of 2011 to accommodate different models of cell phones.

However, the release plan is still in its early stages. In order to place the product on the public market, the chip must prove to be consistently accurate, without triggering false alarms that the user might learn to ignore. So far, to ensure that the sensor is reliable, the lab has conducted sensitivity tests by pumping gases over the chip and recording how often it responded to various chemicals. Sailor said he thinks the chip is infallible.

“Our biggest advantage with our sensor is it doesn’t foul,” Sailor said.

The team is currently working to improve the sensitivity of the chip, as well as widen the range of airborne chemicals it can detect.

Readers can contact Jake Boissonault at [email protected].