In 2019, researchers at the University of Illinois Urbana-Champaign were working on a rapid test that could detect horse respiratory viruses in less than 30 minutes using a nasal swab and a smartphone. When the COVID-19 outbreak began later that fall, the team was able to pivot quickly to include the SARS-CoV-2 virus among the pathogens that could be identified.

Their early study on COVID-19 was published in Lab on a Chip in April 2020, and in 2021 that paper was among the top 3% most cited Royal Society of Chemistry publications. It has been cited in many peer-reviewed journals, including ACS Nano and Scientific Reports.

“The timing was really good,” said Brian Cunningham, the Intel Alumni Endowed Chair in Electrical and Computer Engineering and one of the study’s authors. “We were already working on how to use mRNA to detect viruses quickly with an inexpensive device that everyone has (a smartphone), so we were able to transition to COVID-19 easily. Our paper may have been the first to show this capability.”

Before the pandemic began, the team was already testing the diagnostic tool on horses located on UIUC’s Veterinary Medicine campus. Horses and other animals experience a viral transmission process similar to that of humans, and the interventions for suppressing disease spread – quarantining and distancing from others – are much the same. When the COVID-19 outbreak occurred, the scientists were able to parlay their work to include the SARS-CoV-2 strain.

Cunningham said the research’s magic sauce was in the detection process. Unlike polymerase chain reaction (PCR) tests, which are often considered the gold standard for virus detection, the UIUC test focused on nucleic acids. For that reason, the team was able to create a test that could work with samples at the same temperature for 30 minutes. PCR tests, on the other hand, must cycle among various temperatures – one reason why they require certain lab conditions and special equipment.

“Our test gives an answer really quickly,” Cunningham said. “And instead of having to use really expensive diagnostic tools in a laboratory, we were able to get similar results from a smartphone in the field.”

In addition to Cunningham, the authors include Grainger Engineering Dean Rashid Bashir, Animal Sciences Professor Matthew Wheeler, Bioengineering Research Scientist Anurup Ganguli, and graduate students Fu Sun (first author), Judy Nguyen, Ryan Brisbin, Krithika Shanmugam, and David L. Hirschberg. David M. Nash also contributed. The initial work was funded by the National Science Foundation.

Cunningham said that since the paper’s publication, his group has developed a second method for detecting COVID-19 and other viruses. While the original method broke the virus open to access its nucleic acid, the new process can detect the intact virus.

“The new test is better, faster, and more sensitive and can detect COVID-19 in five minutes at room temperature,” Cunningham said. “It’s a new technique, and we’re really excited about its possibilities.”