Table 1.
Retention times (RT), selected reaction monitoring (SRM) transitions, and collision energies (CE) used for UHPLC-MS/MS quantitative analysis and concentrations of calibration curve standards spiked into blank human seruma
| Isoflavone | RT, min | SRM transition, m/z (Polarity) | CE, V | Standard curve concentrations, ng/mL | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Genistein | 2.06 | 271 → 153 (+) | 28 | 0.3 | 0.9 | 1.8 | 5.4 | 16.2 | 48.6 | 145.8 | 437.4 | 1312 |
| 269 → 133 (-) | 31 | |||||||||||
| Daidzein | 1.39 | 255 → 199 (+) | 24 | 0.07 | 0.2 | 0.6 | 1.8 | 5.4 | 16.2 | 48.6 | 145.8 | 437.4 |
| 255 → 137 (+) | 26 | |||||||||||
| Biochanin A | 3.76 | 285 → 213 (+) | 37 | 0.1 | 0.3 | 0.6 | 1.8 | 5.4 | 16.2 | 48.6 | 145.8 | 437.4 |
| 285 → 270 (+) | 25 | |||||||||||
| Irilone | 3.15 | 299 → 123 (+) | 36 | 0.3 | 0.9 | 1.8 | 5.4 | 16.2 | 48.6 | 145.8 | 437.4 | 1312 |
| 299 → 181 (+) | 26 | |||||||||||
| Prunetin | 3.74 | 285 → 242 (+) | 32 | 0.1 | 0.3 | 0.6 | 1.8 | 5.4 | 16.2 | 48.6 | 145.8 | 437.4 |
| 285 → 167 (+) | 28 | |||||||||||
| Formononetin | 2.69 | 269 → 197 (+) | 37 | 0.02 | 0.07 | 0.2 | 0.6 | 1.8 | 5.4 | 16.2 | 48.6 | 145.8 |
| 269 → 253 (+) | 28 | |||||||||||
| d4-Daidzein | 1.35 | 259 → 203 (+) | 25 | |||||||||
| 259 → 95 (+) | 38 | |||||||||||
| d4-Genistein | 2.01 | 275 → 219 (+) | 26 | |||||||||
| 273 → 137 (-) | 31 | |||||||||||
a
The first SRM transition was used as the quantifier while the second SRM transition was used as a qualifier.