Table 3.
Rate (k) and Equilibrium Constants (K) Characterize the Formation of [Ga(DOTA)]−, [Ce(DOTA)]−, [Eu(DOTA)]−, [Y(DOTA)]−, and [Lu(DOTA)]− Complexes in H2O and 10, 40, and 70 vol % EtOH Solutions (0.15 M NaCl, 25°C)
| H2O | 10 vol % EtOH | 40 vol % EtOH | 70 vol % EtOH | ||
|---|---|---|---|---|---|
| [H2O] (mol L−1) | 55.6 | 50.1 | 33.9 | 16.9 | |
| Kw | 1.4 × 10−14 | 1.1 × 10−14 | 5.4 × 10−15 | 2.3 × 10−15 | |
| [Ce(DOTA)] | M(HL)kH2O (M−1 s−1) | 0.34a | 0.42 ± 0.03 | 0.43 ± 0.04 | 0.4 ± 0.1 |
| M(HL)kOH (M−1 s−1) | (1.9 × 107)15 | (1.1 ± 0.5) × 107 | (1.5 ± 0.3) × 107 | (9 ± 3) × 106 | |
| log KM(HL)H | 8.64a | 8.9(1) | 8.5(2) | 7.9(3) | |
| [Eu(DOTA)] | M(HL)kH2O (M−1 s−1) | 1.46 ± 0.09 | 1.49 ± 0.05 | 1.4 ± 0.1 | |
| M(HL)kOH (M−1 s−1) | |||||
| log KM(HL)H | 8.7(1) | 8.4(2) | 7.8(2) | ||
| [Y(DOTA)] | M(HL)kH2O (M−1 s−1) | 1.49 ± 0.08 | 1.47 ± 0.07 | 1.37 ± 0.09 | |
| M(HL)kOH (M−1 s−1) | (4.8 ± 0.8) × 109 | (4.2 ± 0.7) × 109 | (4.4 ± 0.09) × 109 | ||
| log KM(HL)H | 8.60(3) | 8.47(2) | 8.13(5) | ||
| [Lu(DOTA)] | M(HL)kH2O (M−1 s−1) | 4.70 ± 0.08 (Yb3+: 4.4)a | 4.64 ± 0.09 | 4.68 ± 0.05 | |
| M(HL)kOH (M−1 s−1) | (1.1 ± 0.3) × 109 | (1.0 ± 0.4) × 109 | (1.5 ± 0.6) × 109 | ||
| log KM(HL)H | 8.40(2) (Yb3+: 8.4)a | 8.36 (2) | 8.15(1) | ||
| [Ga(DOTA)] | M(HL)kH2O (M−1 s−1) | 0.82 ± 0.07 | 1.00 ± 0.09 | 0.90 ± 0.05 | |
| M(HL)kOH (M−1 s−1) | (1.3 ± 0.1) × 1011 | (9 ± 1)×1010 | (1.0 ± 0.4) × 1011 | ||
| log KM(HL)H | 7.16(4) | 7.09(3) | 6.75(3) |
a
Reference 15.