INDIANAPOLIS — Not feeling well? A new sensor can tell the difference between a case of the flu or COVID-19 in just 10 seconds. Researchers say it can differentiate between various virus strains and infections in about the time it takes to sneeze. The device also detects their presence at much lower levels and much more quickly than conventional tests.
Only a square inch in size, its key component is a tiny nanomaterial no thicker than an atom. Symptoms of both flu and COVID overlap considerably, making them difficult to distinguish, researchers explain.
“When both of these viruses are circulating together as they did earlier this winter, it would be immensely useful to have a sensor that can simultaneously detect whether you have COVID, flu, none of the above or both,” says project leader Dr. Deji Akinwande in a media release.
The University of Texas at Austin team adds their device could be modified to test for other infections as well. They constructed it using graphene, a single layer of carbon atoms arranged in a hexagonal lattice pattern. Its extreme thinness renders it highly sensitive to any electrical changes in its environment. The breakthrough opens the door to create sensors for a range of applications, other than disease testing.
“These ultra-thin nanomaterials generally hold the record for best sensitivity, even down to the detection of single atoms, and they can improve the ability to detect very small quantities of basically anything that needs to be sensed, whether it’s bacteria or viruses, in gas or in blood,” Akinwande says.
The research group previously designed a graphene-based temporary tattoo that could monitor blood pressure. It consists of pairs of sensors placed along the arteries of the arm. One sends out an electrical current that its partner detects — determining blood flow.
The new infection sensor responds to the presence of viral proteins produced by the immune system. The researchers linked antibodies against SARS-CoV-2, the virus that causes COVID, and flu to graphene. When scientists place a sample from an infected person on the device they bind to their target proteins, prompting a change in the electrical current.
For safety reasons, the researchers tested the sensor using virus proteins delivered in fluid resembling saliva. Results indicated it identified their presence, even in extremely low quantities. The high sensitivity suggests that the sensor could help detect the sparse viral particles found when an infected person breathes.
In comparison to conventional COVID-19 tests that can take minutes or hours, depending on the type, Dr. Akinwande’s device does this almost instantaneously. A dual COVID and flu test recently authorized by the U.S. Food and Drug Administration takes about half an hour to produce results.
The researchers are working to improve its performance further by expanding the slate of viruses it can detect. They are also developing a sensor designed to test for SARS-CoV-2 variants, such as Omicron and Delta. While they are currently focusing on a two-variant design, the test could be adapted to simultaneously identify even more.
Researchers presented these findings at the spring meeting of the American Chemical Society.
South West News Service writer Mark Waghorn contributed to this report.