Table 2.
Parameters of the used UPLC-UV and UPLC-MS method for tacrolimus quantification. MP = mobile phase.
| MS Method | UV Method | ||||
|---|---|---|---|---|---|
| Column | Kinetex 2.6 µm XB-C18 100A 50 × 2.1 mm | Acquity UPLC BEH-C18 1.7 µm 50 mm × 2.1 mm | |||
| Flow (mL/min) | 0.6 | 0.8 | |||
| Column temperature (°C) | 55 | 60 | |||
| Injection volume | 5 | 80 | |||
| Time (min) | MP 1 (%) | MP 2 (%) | Time (min) | MP 3 (%) | MP 4 (%) |
| 0 | 25 | 75 | 0 | 55 | 45 |
| 0.5 | 97.5 | 2.5 | 8 | 45 | 55 |
| 2 | 25 | 75 | 8.5 | 55 | 45 |
| 3.2 | 25 | 75 | 12 | 55 | 45 |
| Detection | Tacrolimus-NH4 | 821.7 → 768.6 | UV | 210 nm | |
| Tacrolimus-NH4 D5 | 826.6 → 773.6 | ||||
Mobile phase 1 = Acetonitrile, mobile phase 2 = Ammonium acetate 2 mM + 0.1% formic acid in water, mobile phase 3 = 90% water with 1% trifluoroacetic acid—10% acetonitrile, mobile phase 4 = 90% acetonitrile—10% water.