Table 1.
Assay performance parameters at representative points along the dynamic range.
| [1,25(OH)2D3] (ng/mL) | Accuracy (%) |
Precision (%) |
Recovery (%) |
|---|---|---|---|
| Plasma | |||
| 0.1 | 95.0 | 2.5 | - |
| 1.0 | 110.7 | 1.9 | 92.2 (11.4) |
| 10 | 97.4 | 0.4 | - |
| 100 | 87.3 | 2.1 | - |
| Tumor homogenate | |||
| 0.1 | 110.7 | 2.9 | - |
| 0.3 | 105.0 | 2.6 | - |
| 1.0 | 89.6 | 0.8 | 11.0 (16.1) |
| 3.0 | 96.3 | 1.2 | - |
Assay performance was assessed in triplicate using samples that contained the indicated concentrations of 1,25(OH)2D3. Precision was calculated as the relative standard deviation. Accuracy was calculated as the back-calculated concentration relative to the nominal concentration. Extraction recovery was assessed at 1 ng/mL 1,25(OH)2D3 and was calculated as the relative response of an extracted sample versus the response of a standard in mobile phase.