Researchers are developing color-changing stickers for masks to detect COVID-19

As COVID-19 continues to spread, researchers are looking for new and creative ways to help detect and manage cases. A team at the University of California San Diego is developing something to help do just that: a color-changing sticker. 

The sticker is a test strip and blister pack that can be placed on N95, surgical or cloth masks and detect SARS-CoV-2 in the user's breath or saliva, according to a news release from the university. 

As the person wearing the mask breathes, the test strip aims to detect protein-cleaving molecules produced from a COVID-19 infection. Once the user removes the mask and test materials, they squeeze out the contents of the blister pack onto the test strip. If the test strip turns a specific color, it means infection molecules are present. 

The university says the test would be similar to that of a home pregnancy test, with the test strip having a control line that shows what a positive result will look like. 

Jesse Jokerst, professor of nanoengineering at the UC San Diego Jacobs School of Engineering and lead principal investigator of the project, noted that the strips will not replace standard testing protocols.

"Think of this as a surveillance approach, similar to having a smoke detector in your house," Jokerst said in the news release. "This would just sit in the background every day and if it gets triggered, then you know there's a problem and that's when you would look into it with more sophisticated testing."

Jokerst and researchers at UC San Diego School of Medicine aim to test the strips on positive COVID-19 saliva samples before they're tested on patients and health care workers. 

The aim of the project, UCSD said in its news release, is to help provide "simple, affordable and reliable surveillance for COVID-19 infections that can be done daily and easily implemented in resource-poor settings." 

Jokerst said masks are the "perfect 'wearable' sensor for our current world." 

"We're taking what many people are already wearing and repurposing them," Jokerst said, "so we can quickly and easily identify new infections and protect vulnerable communities."

The tests are expected to cost only a few cents per strip to produce, making them affordable for daily testing, particularly in facilities that are high-risk for the spread of coronavirus, such as prisons, homeless shelters and dialysis clinics. 

And should pandemics emerge in the future, Jokerst said, "it would not be too far of a stretch to imagine that we could still benefit from this work."