Table 2.
Limit of detection (LOD) of dansyl (DS), picolinoyl (P), pyridine-3-sulfonyl (PS), and 1-methylimidazole-2-sulfonyl (IS) derivatives by orbitrap LC/MS in full scan (FS) and targeted selected ion monitoring (tSIM) mode.
|
DS
|
P
|
PS
|
IS
|
|||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| tR (min) | LOD (pg/ml) | tR (min) | LOD (pg/ml) | tR (min) | LOD (pg/ml) | tR (min) | LOD (pg/ml) | |||||
| FS | tSIM | FS | tSIM | FS | tSIM | FS | tSIM | |||||
| Test | 3.8 | 13 | 22 | 14.4 | 65 | ND | 11.5 | 3 | 10 | 7.5 | 6.4 | 12 |
| Prog | 9.1 | 26 | 15 | 14.8 | 200 | 18.1 | 11 | 6.6 | 13.8 | 4.5 | 11 | |
| E3 | 10.7 | 3.6 | 2.3 | 13.5 | 6.3 | 5 | 10.8 | 2.9 | 0.2 | 5.2 | 1.9 | 0.8 |
| 16epi-E3 | 13.8 | 2.7 | 1.8 | 13.3 | 7.5 | 4.0 | 12.4 | 2.5 | 0.2 | 7.1 | 1.2 | 0.6 |
| 17epi-E3 | 14.5 | 6.1 | 2.4 | 13.4 | 23 | 5 | 12.9 | 5.3 | 0.2 | 7.7 | 1.8 | 0.9 |
| 16ketoE2 | 13.6 | 3.7 | 2.1 | 12.8 | 46 | 17 | 12.3 | 11 | 0.6 | 7.1 | 1.4 | 0.3 |
| 16α-OHE1 | 13.9 | 6.0 | 3.1 | 13.1 | 78 | 23 | 12.6 | 13 | 0.9 | 7.4 | 2 | 0.4 |
| 2MeOE2 | 17.7 | 8.1 | 0.6 | 16.5 | 16 | ND | 16.7 | 4 | 3 | 11.1 | 1.4 | 0.1 |
| 4MeOE2 | 18.0 | 2.0 | 0.5 | 16.3 | 85 | ND | 16.2 | 20 | 2.4 | 10.5 | 1.6 | 0.1 |
| E2 | 18.2 | 2.0 | 0.6 | 16.5 | 5 | 16 | 16.4 | 6.2 | 11 | 10.7 | 0.9 | 0.4 |
| E1 | 19.8 | 2.8 | 6.4 | 14.0 | 5.3 | 3 | 19.3 | 1.9 | 4.4 | 12.3 | 0.7 | 0.1 |
| 3OMeE1 | 18.3 | 2.4 | 7.5 | 13.8 | 3.2 | ND | 18.2 | 3.3 | 6.4 | 12.3 | ND | ND |
| 2MeOE1 | 19.2 | 13 | 8.6 | 14.1 | 20 | ND | 19.5 | 5.6 | 12 | 12.8 | 2.6 | 0.7 |
| 4OMeE1 | 19.7 | 3.7 | 7.7 | 13.9 | 9.5 | ND | 19.3 | 20 | 15 | 12.3 | ND | ND |
| 4OH-E2 | 21.8 | 49 | 10 | ND | ND | ND | ND | 8.3 | 5.7 | 4.5 | ||
| 2OH-E2 | 22.9 | 15 | 3.0 | 14.8 | 200 | ND | 19.9 | 21 | 6 | 9.2 | 1.4 | 1 |
| 4OH-E1 | 24.2 | 19 | 1.7 | 12.0 | ND | ND | 16.0 | 30 | 5.1 | 10.0 | 1.5 | 0.03 |
| 2OH-E1 | 24.5 | 20 | 1.5 | 12.5 | 13 | 11 | 16.9 | 27 | 4 | 10.6 | 1.2 | 0.02 |
LODs were determined using signal to noise ratio (S/N = 3).
ND = not determined.