The efficacy of wtSPIDAR and mSPIDAR to dissociate the binding of SARS-CoV-2 spike S1 with ACE2 was investigated using the ACE2:SARS-CoV-2 Spike inhibitor screening assay kit (BPS Bioscience, San Diego, CA) according to manufacturer’s instructions as described by us recently (11 (link)). Briefly, 96-well nickel-treated plate provided by the manufacturer was coated with ACE2 solution. After washing with immuno buffer and treatment with blocking buffer, different concentrations of wtSPIDAR and mSPIDAR were added to each well followed by addition of SARS-CoV-2 Spike (RBD)-Fc. After washing and incubation with blocking buffer, plates were treated with anti-mouse Fc-HRP followed by addition of an HRP substrate. Resultant chemiluminescence was monitored in a Perkin Elmer multimode microplate reader, Victor X5.