The results of the new multi-institutional study, led by University of Illinois at Urbana-Champaign electrical and computer engineering professor Brian Cunningham and bioengineering professor Rashid Bashir, are reported in the journal Lab on a Chip.

“The challenges associated with rapid pathogen testing contribute to a lot of uncertainty regarding which individuals are quarantined and a whole host of other health and economic issues,” Cunningham said.

The study began with the goal of detecting a panel of viral and bacterial pathogens in horses, including those that cause severe respiratory illnesses similar to those presented in COVID-19, the researchers said.

“Horse pathogens can lead to devastating diseases in animal populations, of course, but one reason we work with them has to do with safety. The horse pathogens in our study are harmless to humans,” Cunningham said.

The new testing device is comprised of a small cartridge containing testing reagents and a port to insert a nasal extract or blood sample, the researchers said. The whole unit clips to a smartphone.

Inside the cartridge, the reagents break open a pathogen’s outer shell to gain access to its RNA. A primer molecule then amplifies the genetic material into many millions of copies in about 10 or 15 minutes, the researchers said. A fluorescent dye stains the copies and glows green when illuminated by blue LED light, which is then detected by the smartphone’s camera.