Table 5.
Short-term and long-term stability of FMP products of vitamin D3 metabolites in serum extract
| Stability |
t = 0 |
24 h, −20°C |
1 week, −80°C |
||||
|---|---|---|---|---|---|---|---|
| Analyte | Spiked concentration (ng/ml) | Mean accuracy (R%) | %CV | Mean accuracy (R%) | %CV | Mean accuracy (R%) | %CV |
| 24,25(OH)2D3 | 0.5 | 99 | 9.0 | 107 | 4.6 | 97 | 8.0 |
| 8 | 95 | 1.3 | 91 | 2.0 | 87 | 1.5 | |
| 35 | 94 | 5.2 | 90 | 2.1 | 85 | 8.1 | |
| 1,25(OH)2D3 | 0.5 | 107 | 4.4 | 104 | 2.9 | 95 | 4.4 |
| 5 | 99 | 3.8 | 93 | 1.5 | 93 | 3.5 | |
| 9 | 95 | 1.4 | 93 | 1.8 | 92 | 1.2 | |
| 3β-25(OH)D3 | 8 | 110 | 3.6 | 98 | 3.0 | 77 | 9.3 |
| 50 | 106 | 2.6 | 93 | 7.4 | 82 | 1.9 | |
| 90 | 102 | 1.4 | 90 | 3.2 | 75 | 4.7 | |
| 3α-25(OH)D3 | 0.5 | 102 | 4.0 | 97 | 2.4 | 76 | 7.1 |
| 8 | 99 | 2.3 | 90 | 4.5 | 75 | 3.0 | |
| 18 | 100 | 3.3 | 95 | 2.8 | 79 | 4.6 | |
| D3 | 8.7 | 105 | 2.2 | 99 | 5.8 | 77 | 9.8 |
| 50.7 | 108 | 5.2 | 101 | 5.6 | 85 | 7.7 | |
| 90.7 | 103 | 3.9 | 99 | 4.0 | 74 | 8.2 | |