Development and Validation of Stability-indicating HPLC Method for Roflumilast and Related Substances

A reversed phase HPLC method was developed and validated for analysis of roflumilast, its related substances and degradation products, using Ecosil C18 column (250x4.6 mm, 5 mu m) with a flow rate of 1.0 ml/min and detection wavelength of 215nm. The mobile phase was a mixture of acetonitrile and 0.005mol.L-1 ammonium dihydrogen phosphate buffer pH 3.5 in the ratio of 48:52 (v/v). The samples were analyzed using 20 mu l injection volume and the column temperature was maintained at 30 C. The limit of detection and limit of quantitation were found to be 2.6 ng/ml and 8ng/ml, respectively. The stability-indicating capability of method was established by forced degradation studies and method demonstrated successful separation of drug, its related substances and degradation products. The method is sensitive, specific, accurate, precise and stability indicating for the quantitation of drug, its related substances and other degradation compounds.