Table 2. Binding Affinity between the LL-37 & HNP1-Attached GQDs and SARS-CoV-2 S1 Protein RBD (Different Variants) Measured by Fluorescence Quenching and ELISA Assays.

system	GQD-based fluorescence quenching	ELISA-like assay
alpha B.1.1.7 variant spike-RBD	13 ± 1 nM	14 ± 1 nM
beta B.1.351 variant spike-RBD	11 ± 1 nM	11 ± 1 nM
gamma P.1 variant spike-RBD	12 ± 1 nM	12 ± 1 nM
delta B.1.617.2 variant spike-RBD	8 ± 1 nM	9 ± 1 nM