July 27, 2022 - Podcast

Episode 291 — The future of COVID-19 testing

As the BA.5 omicron variant continues to spread, health experts are increasingly preparing for a future in which such COVID-19 variants emerge, surge and recede similar to the seasonal flu. An important part of staying on top of these changes will be the ability to quickly monitor the virus at a "population scale," an effort that will require accurate and ultra-fast testing. To help meet this challenge, researchers from the School of Science at IUPUI are developing a new biosensor with the potential to achieve the speed and efficiency required for the future of COVID-19 testing. The work was recently reported in Applied Materials & Interfaces, a journal of the American Chemical Society. It is led by Chemistry and Chemical Biology Professor Rajesh Sardar and Adrianna Masterson, who was a graduate student in Sardar's lab at the time of the study. Sardar says high-throughput testing is so sought-after because this type of high-speed analysis will be essential to protecting against COVID-19 as the virus evolves. Sardar says his lab’s technology is particularly fast, efficient, accurate and unprecedentedly sensitive. In terms of speed, the COVID-19 test from Sardar's lab can currently analyze samples from 96 individuals in under three hours. In terms of efficiency, the system requires only 10 microliters of blood. By comparison, a typical blood panel order by a primary-care physician collects 10 milliliters of blood -- over 1,000 times more. Based upon a blind analysis, the researchers found their biosensor's accuracy rate was 100 percent and its specificity rate was 90 percent. In other words, the sensor never reported a false negative and only reported a false positive in 1 out of 10 samples. Sardar says for the purposes of public safety, the absence of false negatives is more important than false positives, because a person with a false negative may unknowingly infect others, whereas a person with a false positive is not a danger. Additionally, Sardar says the sensor was found to be highly accurate at measuring the body's COVID-19 antibody concentration. This is because it detects not only the virus's spike protein but also the proteins created by the body to protect against the virus. He says the ability to measure COVID-19 antibodies is significant because many COVID-19 antibody tests currently authorized by the FDA don't provide specific antibody counts, despite the fact that this number indicates the strength of a person's immunity to infection. This work, which began in the early days of the pandemic, builds upon initial promising results published in June 2021. Sardar says he aims to further refine the technology, with a goal of eventually being able to process 384 samples in less than an hour -- or 5,000 samples per day, if used in a larger testing center.