New low-cost sensor can detect diseases just from your breath

Scientists have developed a low-cost, disposable sensor that can detect disease markers in one's breath, giving patients an early warning sign to call the doctor. The small-sized device is made of a thin square of an organic plastic, researchers said.

"We developed this method to directly print tiny pores into the device itself so we can expose these highly reactive sites. By doing so, we increased the reactivity by ten times and can sense down to one part per billion," said Ying Diao, professor at University of Illinois at Urbana-Champaign in the US.

"We want to hand out a cheap sensor chip to patients so they can use it and throw it away," Diao said. Researchers, including those from Purdue University in the US, focused on ammonia as a marker for kidney failure. Monitoring the change in ammonia concentration could give a patient an early warning sign to call their doctor for a kidney function test, researchers said.

Researchers chose a material that is highly reactive to ammonia but not to other compounds in breath. However, by changing the composition of the sensor, they created devices that tuned to other compounds. For example, the researchers created an ultrasensitive environmental monitor for formaldehyde, a common indoor pollutant in new or refurbished buildings.

"We would like to be able to detect multiple compounds at once, like a chemical fingerprint. It is useful because in disease conditions, multiple markers will usually change concentration at once," Diao said. "By mapping out the chemical fingerprints and how they change, we can more accurately point to signs of potential health issues," she added. The study was published in the journal Advanced Functional Materials.