Table 3 Robustness assessment of the proposed chromatographic methods
Parameters tested | HPTLC method | Parameters tested | HPLC method | ||||||
|---|---|---|---|---|---|---|---|---|---|
VON | ASP | VON | ASP | ||||||
RSD % peak areas | Rf ± SD | RSD % peak areas | Rf ± SD | RSD % peak areas | Rt ± SD | RSD % peak areas | Rt ± SD | ||
1) Mobile phase composition [Ethyl acetate: ethanol: Ammonia (5:5:0.05, 5.5:4.5:0.05, 4.5:5.5:0.05, 5:5:0.1 (v/v))] | 1.04 | 0.54 ± 3.85 × 10–2 | 0.85 | 0.83 ± 2.05 × 10–2 | 1) Mobile phase ratio [± 0.5% aqueous phase] | 0.99 | 6.60 ± 4.04 × 10–2 | 1.20 | 2.51 ± 1.64 × 10–2 |
2) Mobile phase volume [15, 20 and 25 mL] | 0.89 | 0.54 ± 1.00 × 10–2 | 0.99 | 0.83 ± 5.48 × 10–3 | 2) Flow rate [1 ± 0.05 mL/min] | 0.89 | 6.60 ± 5.22 × 10–2 | 1.22 | 2.50 ± 1.34 × 10–2 |
3) Duration of saturation [30, 40 and 50 min] | 0.94 | 0.55 ± 8.95 × 10–3 | 1.20 | 0.84 ± 1.10 × 10–2 | 3) Column temp. [25o C ± 5o C] | 1.20 | 6.59 ± 1.14 × 10–2 | 1.17 | 2.50 ± 4.47 × 10–3 |
4) Time from chromatography to scan [10, 20, 30 and 60 min] | 1.25 | 0.57 ± 4.47 × 10–2 | 1.24 | 0.84 ± 8.94 × 10–3 | 4) pH of the aqueous phase [6.8 ± 0.2] | 1.55 | 6.57 ± 2.74 × 10–2 | 0.89 | 2.51 ± 1.41 × 10–2 |
5) λ (± 2 nm) | 1.01 | 0.54 ± 8.37 × 10–3 | 0.99 | 0.84 ± 1.79 × 10–2 | 5) λ (± 2 nm) | 1.01 | 6.60 ± 2.17 × 10–2 | 1.50 | 2.50 ± 8.37 × 10–3 |