As shown in Fig1 & Tab1, for medium-affinity samples (mostly antigen-antibody), the detection results (KD) of BLI and SPR are almost consistent. For high-affinity samples, due to limitations in instrument stability and sensitivity, BLI may show artificially high detection results or fail to detect. For low-affinity samples (fast on and fast off, such as most small molecules and peptides), due to sensitivity limitations, BLI may fail to detect.
Human IgG-1
Human IgG-2
Human IgG-3
Figure 1 Affinity binding curves of human IgG-1, 2, 3
Table 1 Affinity binding detailed analysis report of human IgG-1, 2, 3
| Ab | Chip | Affinity | Test item | Chi² (RU²) | Ka (1/Ms) | kdis (1/s) | KD (M) |
|---|---|---|---|---|---|---|---|
| Human IgG-1 | ProA | Medium | Affinity | 4.90e-02 | 1.39e+05 | 2.07e-03 | 1.49e-08 |
| Human IgG-2 | ProA | High | Affinity | 3.41e-01 | 2.75e+04 | 3.59e-05 | 1.30e-09 |
| Human IgG-3 | ProA | Low | Kinetics | 4.75 | - | - | 3.818E-07 |
