Binding Constants of Affibody Analogs 5, 7, 9, and 11 Toward Human HER2
| Compound | ka (1/Ms) | kd (1/s) | KD (nM) | Average KD (nM) |
| 5 | 1.27e6 | 5.21e−4 | 0.40 | 0.36 |
| 1.52e6 | 4.81e−4 | 0.32 | ||
| 7 | 1.99e6 | 7.92e−4 | 0.40 | 0.40 |
| 2.04e6 | 8.21e−4 | 0.40 | ||
| 9 | 2.66e6 | 9.26e−4 | 0.35 | 0.48 |
| 1.7e6 | 1.02e−3 | 0.60 | ||
| 11 | 2.56e6 | 4.30e−4 | 0.17 | 0.18 |
| 2.59e6 | 5.66e−4 | 0.19 |
Kinetic or rate constants, association rate constant ka and dissociation rate constant kd, describe rate of formation or dissociation of complex, and kinetic parameters can be evaluated from association and dissociation phases of sensorgram. KD is determined from kinetic parameters.