Interaction of VEGFR-2 (A) or HER-2 (B) or EGFR (C) or 6×his-tag (D) with MdOS by surface plasmon resonance analysis.

VEGFR2 was injected at the concentrations of 2.56, 0.64, 0.32, 0.16 and 0.08 µM (from top to bottom); HER-2 was injected at the concentrations of 0.53, 0.26, 0.13, 0.07 and 0.03 µM (from top to bottom); EGFR was injected at the concentrations of 6, 3, 1.5, 0.75, 0.38, 0.19 and 0.09 µM (from top to bottom); 6×his-tag was injected at the concentrations of 100, 10, 1, 0.1, 0.01 µM. Sensorgram responses at equilibrium were plotted against each concentration of compounds and the equilibrium dissociation constant (K_D) of the binding system was calculated using BIAeval software 3.1.