Six months into battling the Covid-19 pandemic, it’s clear that the US still needs better testing. Backlogs have caused unbearably long wait times for results, and the coming flu season might further encumber test processing. But what if our coronavirus-carrying breath could be harnessed to detect Covid-19? That’s the hope of some researchers at Ohio State University and Northeastern University, who are developing Covid-19 breathalyzer devices.
Most people know breathalyzers as the handheld tools toted by police officers for determining alcohol intoxication; but scientists wield them too—just not for sobriety tests. Researchers have explored using them, and similar devices, to analyze exhaled breath for indicators of diabetes, certain cancers, respiratory diseases, and many other conditions.
Now, researchers like Ohio State University engineering professor Perena Gouma say a similar approach might work for Covid-19 and could offer key advantages over the current gold standard, polymerase chain reaction (PCR) tests based on throat or nose swabs. A breathalyzer needs no reagents nor laboratory processing and could provide rapid results. This kind of test “is noninvasive and nonintrusive,” Gouma says. “You can deploy it wherever, whenever.” While there aren’t any on the market yet for Covid-19 testing, her lab and others are conducting trials on people and hope to gain approval from the Food and Drug Administration for broader use.
Gouma has been studying breath analysis, sensors, and diagnostic devices for years. In 2017, she invented a breath-monitoring device aimed at early detection of the flu by primarily targeting the exhaled chemical compound isoprene. Building on this work, she’s now developed a prototype Covid-19 breathalyzer that uses ceramic sensors to detect volatile organic compounds in a person’s breath that she believes act as Covid-19 biomarkers, or disease indicators. Since this work is still unpublished, Gouma won’t say specifically which gaseous molecules her device looks for, only that she and her collaborators came to their conclusions about the likely indicators for Covid-19 after studying the medical literature on other coronavirus diseases and their related biomarkers.
The breathalyzer’s sensors incorporate nanomaterials with high affinity for these biomarkers, meaning the sensors respond only to the target chemical compounds. When users exhale into a disposable mouthpiece attached to the device, the presence of these chemicals in their breath triggers a change in electrical resistance, which the device measures in order to give a reading.
The results take only 15 seconds, Gouma says, and can be transmitted wirelessly or read directly on the device. About a minute later, the breathalyzer is ready for another go. “With this technology, you can monitor the next day and the day after,” Gouma says. “Nothing prevents you from knowing your state of health at any time.”
While the breathalyzer could be used in hospitals or other health care settings, it wouldn’t require specialized training or health care workers to operate, so people at theaters, airports, schools, and other places could also use it, Gouma says. “I envision ubiquitous use of the breathalyzer. That’s what we strive for,” she says.
Development of her breathalyzer received support from a National Science Foundation grant in June. Earlier this summer, Gouma began running a clinical study to test the device at the Ohio State Wexner Medical Center, which included people who had Covid-19 and those who did not. Additional testing is underway that involves participants from various Covid-19 testing sites around Columbus, Ohio. Gouma plans to seek FDA emergency-use authorization for the breathalyzer—which, during public health emergencies, permits use and distribution of certain medical products without full approval.
Earlier this year, Nian Sun, a Northeastern University engineering professor, made the switch from studying gas sensors that detect lung cancer biomarkers to sensors targeting the novel coronavirus. With an NSF grant received in June, Sun and his colleagues have developed a handheld breathalyzer outfitted with electrochemical sensors made to catch viral particles from the air, including from exhaled breath.