Used in research and diagnostic applications to detect the spike protein's receptor-binding domain (RBD) of SARS-CoV-2. Helps in studying virus neutralization mechanisms and evaluating immune responses in infected or vaccinated individuals. Employed in immunoassays such as ELISA, lateral flow tests, and Western blotting for specific identification of the viral RBD. Supports development of therapeutic antibodies and vaccines by characterizing antibody binding and blocking interactions with the human ACE2 receptor.