Table 1.
Analytical and in vitro data of the investigated homotrimeric PSMA conjugates and their corresponding nat/68Ga complexes
| Compound | Analytical HPLCUV/vis/tR mina) | m/zb) | RCYc)/% | Protein binding/% | Serum stability 1 h/% intact | Serum stability 2 h/% intact | IC50d)/nM | 95% CIe) | Cell internalization/% |
|---|---|---|---|---|---|---|---|---|---|
| 7 | 12.1 | 787.6 [M + 2H]2+ | – | – | – | – | 264 | 34.8–2004 | |
| 8 | 14.1 | 957.4 [M + 2H]2+ | – | – | – | – | 65 | 20.2–209 | |
| 9 | 23.5 | 861.9 [M + 3H]3+ | – | – | – | – | 5.9 | 0.86–40.6 | |
| nat/68Ga-7 | 11.4 | 1639.6951 [M-2H]+ | > 99% | 63.8 ± 4.0 | > 96 | > 96 | 450 | 101–2010 | – |
| nat/68Ga-8 | 13.4 | 989.9750 [M-H]2+ | > 99% | 68.2 ± 1.5 | > 97 | > 97 | 90 | 27.0–300 | 0.08 ± 0.02 |
| nat/68Ga-9 | 23.1 | 1324.6272 [M-H]2+ | > 96% | 95.3 ± 0.3 | – | – | 4.8 | 2.4–9.8I | 17.8 ± 2.5 |
a) Retention time, b) mass-to-charge ratio determined by LR- and HR-ESI–MS, c) radiochemical yield, d) half maximum competitive inhibitory concentration, e) CI = confidence interval