①Measured by its binding ability in a functional ELISA. Immobilized SARS-CoV-2-S1-RBD at 2 μg/ml can bind Biotinylated Anti-SARS-CoV-2-S Antibody , the EC50 of SARS-CoV-2-S1-RBD protein is 106.2-131.2 ng/ml.
②Measured by its binding ability in a functional ELISA. Immobilized human ACE2 at 2 μg/ml can bind SARS-CoV-2-S1-RBD, the EC50 of SARS-CoV-2-S1-RBD protein is 8.363-12.82 ng/ml.