Fig. 4From: Single-domain antibodies against SARS-CoV-2 RBD from a two-stage phage screening of universal and focused synthetic librariesAffinity of sdAbs phage clones screened for SARS-CoV-2 RBD binding from the universal sdAb-U library or the target sdAb-RBD library. The statistical difference was measured by paired two-sided Student’s t-test (***, P < 0.001)Back to article page