Table 1.
Concentrations of unconjugated estrogens in postmenopausal serum determined by GC-MS and LC-MS.
| Method | LC-MS | GC-MS | GC-MS | GC-MS | GC-MS | GC-MS | LC-MS | GC-MS | LC-MS | LC-MS | GC-MS | LC-MS | LC-MS | Overall Mean pg/mL |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Derivative | Dansyl | PFBO | PFBO | PFBO | PFBO | PFBO | Dansyl | PFBO | Dansyl | Dansyl | PFBO | Dansyl | NMPS | |
| Reference | 35 | 23 | 24 | 25 | 26 | 27 | 36 | 12 | 37 | 38 | 28 | 39 | Present study |
|
| pg/mL | Mean | Mean | Mean | MeanL | Mean | Mean | Mean | Median | Mean | Median | Mean | Median | Mean | |
| E2 | 15.0 | 3.5 | 7.3 | 3.0 | 6.6 | 4.2 | 15.9 | 3.4 | 3.1 | 4.2 | 3.1 | 2.7 | 2.7 | 5.1 |
| 16α-OH-E2 | 7.9 | x | x | x | x | x | x | x | x | 13.5 | x | 7.7 | BLQ | 10.6 |
| 4-MeO-E2 | BLQ | x | x | x | x | x | x | x | x | BLQ | x | BLQ | BLQ | BLQ |
| 2-MeO-E2 | BLQ | x | x | x | x | x | x | x | x | 1.4 | x | 0.7 | BLQ | 1.0 |
| 4-OH-E2 | x | x | x | x | x | x | x | x | x | x | x | x | BLQ | BLQ |
| 2-OH-E2 | BLQ | x | x | x | x | x | x | x | x | BLQ | x | BLQ | BLQ | BLQ |
X = not determined
BLQ = below LLOQ
PFBO = pentafluorobenzoyl