Table 3:
Instability of [18F]FTP at different radioactivity concentration and growth of unknown side product over time.
| SN | Fatty acid | Radioactivity Concentration (GBq/mL or mCi/mL) | Time of Post synthesis analysis | Peak I (Unknown) | Peak II (Product) | |||
|---|---|---|---|---|---|---|---|---|
| Retention Time (min) | Relative Percentage | Retention Time | Relative Percentage | |||||
| 1 | [18F]FTP | High conc. (1.395 GBq/mL or 37.7 mCi/mL at time zero) | 1.3 GBq/mL (35.4 mCi/mL) | 10 min | 4.53 | 4.2% | 6.13 | 95.8% |
| 0.96 GBq/mL (25.8 mCi/mL) | 60 min | - | - | - | - | |||
| 0.66 GBq/mL (17.7 mCi/mL) | 120 min | 4.45 | 15.5% | 6.13 | 84.5% | |||
| 0.45 GBq/mL (12.1 mCi/mL) | 180 min | 4.33 | 16.4% | 5.97 | 83.6% | |||
| 0.31 GBq/mL ( 8.3 mCi/mL) | 240 min | 4.36 | 17.7% | 5.98 | 82.3% | |||
| Low conc. (0.53 GBq/mL or 14.3 mCi/mL at time zero) | 0.44 GBq/mL (11.8 mCi/mL) | 30 min | 4.54 | 2.6% | 6.09 | 97.4% | ||
| 0.36 GBq/mL (9.8 mCi/mL) | 60 min | - | - | - | - | |||
| 0.25 GBq/mL (6.7 mCi/mL) | 120 min | 4.53 | 6.3% | 6.13 | 93.7% | |||
| 0.17 GBq/mL (4.6 mCi/mL) | 180 min | 4.35 | 10.8% | 5.97 | 89.2% | |||
| 0.12 GBq/mL (3.1 mCi/mL) | 240 min | 4.35 | 10.3% | 5.96 | 89.7% | |||