Figure 4.
The interaction between the influenza HA and quercetin was analyzed with PlexArray HT systems. (A) The binding curve of quercetin with HA protein in SPR assay; (B) The binding curve of curcumin with HA protein in SPR assay. The compounds were immobilized on a sensor chip, and the recombinant influenza HA protein was injected as analytes at various concentrations dissolved in a running buffer at a flow rate of 3 μL/s. The contact time and dissociation time were 300 s respectively. The chip platform was regenerated with gly-HCl (pH 2.0) and washed with the running buffer. Curcumin was used as a positive control in this assay. The affinity constant KD is the ratio of dissociation constant Kd with association constant Ka, KD = Kd/Ka.