Scientists have been working to create breathalyzers that can diagnose various diseases without painful pinpricks, needles, or other unpleasant methods. Now, a UK team has developed a portable breath analyzer that could help doctors diagnose diabetes noninvasively in the office.

Many studies examining the hallmarks of diabetes in exhaled breath have shown that elevated levels of acetone are strongly linked to the disease. However, detecting the concentrations of any given substance in breath in a simple way is a major challenge. Breath contains a complex mix of compounds, including water, carbon dioxide and methane, that can throw results off. Mass spectrometry can do the job, but it is not very practical for point-of-care testing.

Schematic showing how the breathalyzer operates. Researchers led by Robert Peverall, advanced research fellow at the Engineering and Physical Sciences Research Council, created a hand-held device with an adsorbent polymer that can trap acetone from exhaled breath, then release it into a cavity where a laser probes its concentration. They tested the accuracy of the device on the breath of healthy subjects under different conditions, such as after overnight fasting or exercising, and compared results with mass spectrometry readings.

The measurements were a close match and covered a wide range of concentrations, including those that would suggest a patient has either undiagnosed type-1 diabetes or problems controlling their blood glucose. Adding to the practicality of the device, the researchers say it could be re-used many times.