Table 3.
Summary of method validation parameters for curcumin and dexamethasone according to ICH Q2(R1) guidelines.
| Parameter | Acceptance criteria (ICH Q2R1/USP) | Obtained values (this study) | Compliance |
|---|---|---|---|
| Linearity (R²) | R² ≥ 0.99 over at least 5 concentration levels | Curcumin: 0.9999 (0.015–0.25 mg/mL) Dexamethasone: 0.9999 (0.015–0.25 mg/mL) | Pass |
| Accuracy (Recovery %) | 95–105% mean recovery at low, medium, and high levels | Curcumin: 96.5–99.8% (mean 98.7%) Dexamethasone: 96.8–104.3% (mean 101.7%) | Pass |
| Precision (RSD %) | RSD ≤ 2% (repeatability and intermediate precision) | Intra- and inter-day RSD < 2% for all levels | Pass |
| Repeatability (RSD %) | RSD ≤ 2% for replicate injections | RSD < 2% across calibration levels | Pass |
| Robustness | No significant change under minor variations (±0.1 mL/min flow, ±5 nm wavelength, ±5 °C temperature) | RSD < 2% under all tested variations | Pass |
| LOD (mg/mL) | Not specified; typically < 1/3 of LOQ | Curcumin: 0.0035 Dexamethasone: 0.0029 | Meets expectation |
| LOQ (mg/mL) | Demonstrated precision at the lowest quantifiable level | Curcumin: 0.0106 Dexamethasone: 0.0088 | Meets expectation |