SMART researcher Hoi Lok Cheng performs the rapid neutralizing antibody test on the lab prototype. (Credit: Singapore-MIT Alliance for Research and Technology [SMART])

A newly developed paper-based blood test can determine the presence of SARS-CoV-2 neutralizing antibodies within 10 minutes. The point-of-care test offers an accuracy rate of up to 93 percent, which is higher than that of current lab-based methods using COVID-19 convalescent plasma.

The test is portable and easy to operate by a layperson in any setting both inside and outside of laboratories, and only requires a drop of blood, a small amount of liquid reagent, a paper-based assay, and a small device.

As part of a body’s natural immune response, NAbs are generated by either exposure to the virus or a vaccine. For effective prevention of viral infections, NAbs must be generated in sufficient quantities. The number of NAbs present in individuals indicates if they possess protective immunity to the virus and their probability of experiencing severe outcomes should they be infected. NAb testing can determine whether vaccinated individuals should be considered for booster shots for additional protection against the virus.

The test is simple to administer, non-invasive and offers quick results. To perform the test, a user mixes a drop of fingertip blood with the reaction solutions and places it on a paper strip, before inserting it into a portable reader device that will detect the NAb signals and reflect the results. This test offers up to 93% accuracy, higher than similar lab-based methods currently being used.