Fig. 11. Illustration of the LF-sVNT protocol and example sensorgrams. (A) First cycle measuring the binding ability of RBD to ACE2 after neutralization. (B) Second cycle measuring the full binding ability of RBD without neutralization. Reproduced with permission from J. Clin. Microbiol., 2021, 59, e0019321, 10.1128/JCM.00193-21.³⁰⁸.