Abstract

Development and validation of stability indicatingHPLCmethod for adapalene and benzoic acid in pharmaceuticalGel formulations

Author(s): M.Mudasir, N.Tabassum, J.Ali, R.Jan

A simple, selective, precise and stability-indicating high-performance chromatographic method of analysis for adapalene and benzoic acid in pharmaceutical (gel) formulations was developed. Mobile phase consisted of acetonitrile (ACN), tetrahydrofuran (THF) and phosphate buffer (PB) (pH- 3.0; 0.01M). Thismobile phase was found to give adequate results in terms of peak shape, symmetry, tangent and tailing. Retention time (RT) for adapalene and benzoic acid was found to be 8.8 (±1) and 2.2 (±1) respectively. Samples were subjected to acid, alkali hydrolysis, oxidation, thermal, humidity and photodegradation. The whole analysis was carried out at timed wavelength of 230 nm and 272 nm for benzoic acid and adapalene respectively. The linear regression analysis data for the calibration plots showed good linear relationship with r2 = 0.9995 and 0.9998 for adapalene and benzoic acid respectively with respect to peak area respectively in the concentration range of 14-26g/ml for adapalene and 28-52g/ml for benzoic acid. The mean value of correlation coefficient; slope and intercept were 0.9995, 9060.51 and 1282, for adapalene and 0.9998, 10185.77 and 1302 for benzoic acid respectively. Themethod was validated for precision, specificity, recovery and robustness, in accordance with ICH guidelines. The drug undergoes degradation under basic and thermal conditions. This indicates that the drug is susceptible to base hydrolysis, and thermal degradation. Statistical analysis proves that the method is reproducible, selective and accurate for the estimation of said drug. As the method could effectively separate the drug fromits degradation product, it can be employed as a stability-indicating one.