Table 2 Summary of robustness studies
Method/parameter condition | Normal conditions | Normal Rf value | Deliberate changes | Rf ± S.D. (n = 3) | Effect on drug spot |
|---|---|---|---|---|---|
Mobile phase ratio (Methanol: ethyl acetate: toluene: ammonia, v/v/v) | 2:4:4:0.1 | 0.61 | 2:4.5:3.5:0.1 | 0.64 ± 0.01 | Compact band |
2:3.5:4.5:0.1 | 0.59 ± 0.03 | Compact band | |||
Chamber saturation time (min) | 30 | 25 | 0.62 ± 0.01 | Compact band | |
35 | 0.63 ± 0.02 | Compact band | |||
Migration distance (mm) | 80 | 85 | 0.61 ± 0.01 | Compact band | |
75 | 0.62 ± 0.02 | Compact band |