ABSTRACT
We present a net-shaped DNA nanostructure (called "DNA Net" herein) design strategy for selective recognition and high-affinity capture of the intact SARS-CoV-2 virions through spatial pattern-matching and multivalent interactions between the aptamers (targeting wild type spike-RBD) positioned on the DNA Net and the trimeric spike glycoproteins displayed on the viral outer surface. Carrying a designer nanoswitch, the DNA Net-aptamers releases fluorescent signal upon virus binding that is easily read by a hand-held fluorimeter for a rapid (in 10 mins), simple (mix-and-read), sensitive (PCR equivalent), room temperature compatible, and inexpensive (~ $1.26/test) COVID-19 test assay. The DNA Net-aptamers also impede authentic wild-type SARS-CoV-2 infection in cell culture with a near 1,000-fold enhancement of the monomeric aptamer. Furthermore, our DNA Net design principle and strategy can be customized to tackle other life-threatening and economically influential viruses like influenza and HIV, whose surfaces carry class-I viral envelope glycoproteins like the SARS-CoV-2 spikes in trimeric forms.