Table 2.
The stability of plasma samples.
| Stability type | Time and n | Added concentration (μg/L) | Mean measured concentration (μg/L) | Accuracy (%) |
RSD (%) |
|---|---|---|---|---|---|
| Short-term stability | 3 h (n = 3) | 15.63 | 14.30 | 91.5 | 7.0 |
| 125.00 | 131.4 | 105.1 | 5.7 | ||
| 800.00 | 825.5 | 103.2 | 3.0 | ||
| 6 h (n = 3) | 15.63 | 14.22 | 91.0 | 6.8 | |
| 125.00 | 133.6 | 106.9 | 6.2 | ||
| 800.00 | 806.5 | 100.8 | 5.4 | ||
|
| |||||
| Postpreparative stability | 6 h (n = 5) | 15.63 | 14.30 | 91.5 | 7.0 |
| 125.00 | 131.4 | 105.1 | 5.7 | ||
| 800.00 | 825.5 | 103.2 | 3.0 | ||
| 12 h (n = 5) | 15.63 | 15.252 | 97.6 | 9.5 | |
| 125.00 | 130.3 | 104.2 | 6.4 | ||
| 800.00 | 842 | 105.3 | 7.1 | ||
|
| |||||
| Freeze-thaw stability | After 3 freeze-thaw cycles (n = 3) |
15.63 | 13.74 | 87.9 | 7.7 |
| 125.00 | 127.3 | 101.9 | 6.4 | ||
| 800.00 | 771.3 | 96.4 | 4.6 | ||
|
| |||||
| Long-term stability | After 30 days (n = 3) | 15.63 | 13.66 | 87.4 | 5.2 |
| 125.00 | 122.1 | 97.7 | 3.1 | ||
| 800.00 | 804.9 | 100.6 | 4.0 | ||