Table 3.
Configuration of the LC-ESI-MS/MS system.
| Liquid chromatography | |||
| Autosampler temperature | 10 °C | ||
| Injection volume | 2 µL | ||
| Columns | Phenomenex Synergi Max RP, Luna C18 | ||
| Column temperature | 70 °C | ||
| Mobile phase A | 0.1% acetic acid in methanol | ||
| Mobile phase B | 0.1% acetic acid in water | ||
| Gradient program | Time(min) | A (%) | B (%) |
| 0 | 10 | 90 | |
| 3 | 90 | 10 | |
| 4 | 90 | 10 | |
| 4 | 10 | 90 | |
| 6 | 10 | 90 | |
| Flow rate | 500 µL/min | ||
| Mass spectrometry | |||
| Mode | Positive ESI / negative ESI | ||
| Ion spray potential | 5.5– 4.5 kV | ||
| Source temperature | 450 °C | ||
| Scan type | Multiple reaction monitoring | ||
| Dwell time | 10 ms | ||
| Quantification | Relative peak area | ||