Table 3.
Accuracy, precision, and recovery in different matrices
| Low QC (0.5 pg) | High QC (2 pg) | Brain (0.5–4 mg) | Blood (1–20 μl) | Plasma (1–20 μl) | ||
|---|---|---|---|---|---|---|
| E1 | % Recovery (% CV) | 93 (14) | 97 (7) | 102 (5) | 90 (6) | 97 (5) |
| 17β-E2 | % Recovery (% CV) | 97 (5) | 101 (5) | 102 (6) | 94 (8) | 108 (11) |
| 17α-E2 | % Recovery (% CV) | 89 (5) | - - | - - | - - | - - |
| E3 | % Recovery (% CV) | 97 (6) | 95 (5) | 93 (3) | 92 (6) | 102 (7) |
| 4OH-E2 | % Recovery (% CV) | 107 (11) | 78 (16) | 613 (22) | n.d. | 980 (19) |
| 2Me-E2 | % Recovery (% CV) | 96 (13) | 104 (13) | 214 (33) | 295 (3) | 291 (7) |
| 4Me-E2 | % Recovery (% CV) | 99 (8) | 92 (10) | 247 (14) | 200 (5) | 161 (7) |
Accuracy was measured by the recovery of a QC with a known concentration of estrogen. Precision was measured by the coefficient of variation (CV) of replicates. Recovery was assessed for brain, blood, and plasma by comparing unspiked samples with samples spiked with a known amount of steroid. Recovery was not assessed for 17α-E2 and only low QC was used for accuracy and precision so dashes are placed in those cells. n.d. is defined as nondetectable.