Table 6. . Stability of enalapril under different storage conditions (n = 6).
| Serial number | Storage conditions | QC samples (ng/ml) | Mean (ng/ml) | SD | CV (%) | Accuracy (%) |
|---|---|---|---|---|---|---|
| 1 | Autosampler stability 24 h at 24°C | 3 | 2.7500 | 0.4934 | 17.9402 | 92.6446 |
| 200 | 200.9350 | 12.6188 | 6.2800 | 100.4675 | ||
| |
|
400 |
384.6733 |
15.7191 |
4.0863 |
92.6098 |
| 2 | Freeze and thaw stability at -20°C (3 cycles) | 3 | 2.7200 | 0.4528 | 16.6459 | 91.6339 |
| 200 | 189.7283 | 16.5433 | 8.7195 | 94.7244 | ||
| |
|
400 |
388.3750 |
31.0460 |
7.9938 |
93.5010 |
| 3 | Bench top stability for 8 h | 3 | 2.7350 | 0.3092 | 11.3068 | 92.1392 |
| 200 | 200.9567 | 16.9404 | 8.4299 | 100.3303 | ||
| |
|
400 |
412.2483 |
23.03918 |
5.5887 |
99.2485 |
| 4 | Long-term stability at -20.0°C for 30 days | 3 | 2.7000 | 0.5956 | 22.0599 | 90.9601 |
| 200 | 197.6167 | 24.1216 | 12.2062 | 98.6628 | ||
| 400 | 393.2767 | 13.0709 | 3.3236 | 94.6810 |