Table 1.
Selected reaction monitoring (SRM) condition for the major metabolites of the nine cytochrome P450 probe substrates and internal standard (IS).
| P450 Enzyme |
Substrates | Concentration (μM) |
Metabolites | SRM Transition (m/z) |
Polarity | Collision Energy (eV) |
|---|---|---|---|---|---|---|
| 1A2 | Phenacetin | 100 | Acetaminophen | 152 > 110 | ESI+ | 25 |
| 2A6 | Coumarin | 5 | 7-Hydroxycoumarin | 163 > 107 | ESI+ | 17 |
| 2B6 | Bupropion | 50 | 6-Hydroxybupropion | 256 > 238 | ESI+ | 20 |
| 2C8 | Amodiaquine | 1 | N-Desethylamodiaquine | 328 > 283 | ESI+ | 17 |
| Rosiglitazone | 5 | p-Hydroxyrosiglitazone | 374 > 151 | ESI+ | 17 | |
| 2C9 | Tolbutamide | 100 | 4-Hydroxytolbutamide | 287 > 89 | ESI+ | 60 |
| Diclofenac | 10 | 4-Hydroxydiclofenac | 312 > 231 | ESI+ | 15 | |
| 2C19 | Omeprazole | 20 | 5-Hydroxyomeprazole | 362 > 214 | ESI+ | 10 |
| 2D6 | Dextromethorphan | 5 | Dextrorphan | 258 > 157 | ESI+ | 35 |
| 2E1 | Chlorzoxazone | 50 | 6-Hydroxychlorzoxazone | 184 > 120 | ESI− | 18 |
| 3A | Midazolam | 5 | 1′-Hydroxymidazolam | 342 > 203 | ESI+ | 25 |
| IS | Trimipramine | 0.007 | 295 > 100 | ESI+ | 17 |
ESI: Electrospray ionization (ESI) interface to generate protonated ions [M+H]+ or deprotonated ion [M−H]−.