| Protein | kon (M−1∙s−1) | koff (s−1) | Ref. |
| Whale Mb (solution) | 15.9 × 103 | 1.6 | [50] [51] |
| wt-HbI (solution) | 2.30 × 105 | 2.20 × 10−4 | [21] |
| (His)6-rHbI (solution) | 1.90 × 105 | 3.00 × 10−5 | [21] |
| (Lys)6-rHbI (solution) | 1.40 × 105 | 1.00 × 10−4 | [21] |
| (His)6-rHbI (encapsulated) + interacting with H2S (gas) | 0.167 | 8.47 × 10−5 | This work |
| (His)6-rHbI (encapsulated) + interacting with H2S (solution) | 0.0579 | 6.67 × 10−5 | This work |