A Thermoresponsive Magnetic Nanoparticle System Using an Antiviral Lectin for HIV Capture and Concentration

Abstract

Rapid tests have been developed as a method to diagnose HIV infection in resource-limited settings. However, several of these assays suffer from reduced sensitivity due to the limited sample volume. One approach to augment the limit of detection is through concentration of the analyte. We used thermoresponsive poly(N-isopropylacrylamide) (pNIPAAm) conjugated to magnetic nanoparticles (MNP) to concentrate HIV from solution. To target HIV for binding and pull-down, we used a novel strategy employing antiviral lectin cyanovirin-N (CVN) rather than commonly used antibodies. We characterize the construction of a thermoresponsive CVN and CVN mutant, and demonstrate successful binding of HIV by the thermoresponsive CVN mutant and roughly 3.5-fold HIV concentration from a 500 uL sample with greater than 90% efficiency using MNP pNIPAAm. To our knowledge, this is the first evidence of using CVN to bind and concentrate HIV using a thermoresponsive MNP system.