Table 1.
Dissociation constants for HPhen-metal complexes compared to those for free 1,10-phenanthroline (Phen).
| Dissociation Constants (M) | ||||
|---|---|---|---|---|
| HPhen1a | HPhen2a | HPhen3a | Free Phenb | |
| Co2+ | 3.3 (2) × 10−10 | 7.8 (5) × 10−10 | 2.0 (2) × 10−9 | 8.0 × 10−8 |
| Ni2+ | 7.8 (6) × 10−10 | 1.7 (4) × 10−10 | 1.6 (3) × 10−10 | 3.9 × 10−8 |
| Cu2+ | 1.3 (2) × 10−13 | 1.2 (2) × 10−13 | 2.0 (2) × 10−13 | 2.5 × 10−9 |
| Zn2+ | 6 (1) × 10−9 | 3.8 (3) × 10−9 | 3.7 (3) × 10−8 | 3.9 × 10−7 |
a
Dissociation constants determined by competition with EGTA in 50 mM MOPS (pH 7).
b
pH-adjusted values based on reported Kd’s.10