Inside the Yager lab’s at-home medical test kit is a two-dimensional paper network of switches and valves – a microfluidic system that is designed to look for the chemical fingerprints of the suspected disease. The tests could look for antibodies or for bits of a pathogen, such as proteins or DNA or RNA. In one project, the team is looking at the proteins on the outside of flu viruses. Protein test results are ready within 20 minutes.
Looking for nucleic acids makes the test highly sensitive, so the tests can work with people who have a small amount of bacteria or virus in their system. These tests require added steps – they have to break open the cells to get at the DNA or RNA, and then make lots and lots of copies. This takes an extra 20-30 minutes (50 minutes total), but creates enough copies that they can be seen easily on the paper test strip.