Early in the pandemic, when it often took days to get the results back from a COVID test—and relatively few people were getting tested, because of the inconvenience—researchers at MIT and Harvard began adapting wearable sensors that could detect the disease while embedded inside a mask and give a diagnosis within an hour and a half. In a new study in Nature Biotechnology, the researchers showed that their diagnostic masks work as well as the gold standard tests used in labs.
“If testing and sensing at a biological molecular level could be done in a format that can follow people around instead of people having to go to the clinic, maybe you can encourage people to get more testing done,” says Luis Soenksen, a research scientist at Harvard’s Wyss Insitute for Biologically Inspired Engineered and a “venture builder” at MIT’s Abdul Latif Jameel Clinic for Machine Learning in Health who works on helping new technology come to market and is one of the co-authors of the new study. “Basically, you have to wear a mask anyway,” he says. “So why don’t you also have that mask test you at the same time?”
MIT researchers previously created paper tests for Ebola and Zika that use the same core technology, with proteins and nucleic acids embedded in paper that react to target molecules. Another iteration of the system uses CRISPR enzymes to detect target molecules and then change in color, like a pregnancy test. The components are freeze-dried and can stay stable for months—”it’s a little bit like ramen noodles,” says Soenksen—and then come back to life temporary when activated with a small splash of water.
In the prototype mask, a small reservoir of water was also embedded in the mask. The person wearing the mask could push a button to release it and launch the test, which analyzes the droplets from their breath. It avoids the discomfort of using a nasal swab, and the system is very good at detecting the virus. “It’s on par specificity and sensitivity that you will get in a state of the art laboratory, but with no one there,” he says.
In the new study, the scientists showed that the wearable sensors could be embedded in various fabrics and used to test for multiple pathogens. A lab coat, for example, could be embedded with sensors to test for drug-resistant bacteria, so that a doctor working in a hospital could get a warning when exposed. Clothing worn by a soldier could detect nerve agents. The sensors in the masks could be adapted to test for new COVID variants or any other respiratory pathogens.
While many Americans are no longer wearing masks or getting regular tests, the WHO recently recommended that vaccinated people should continue to wear masks now as extra protection as the more transmissible Delta variant spreads. “Our system just allows you to add on laboratory-grade diagnostics to your normal mask wearing,” Peter Nguyen, lead author of the new study and a research scientist at the Wyss Institute for Bioinspired Engineering at Harvard, said via email.”They would especially be useful in situations where local variant outbreaks are occurring, allowing a people to conveniently test themselves at home multiple times a day.” The scientists are now actively looking for industry partners to help bring the masks to market.