10. An improved stability-indicating HPLC method for Riluzole hydrochloride in bulk and pharmaceutical dosage forms

In the present study, a stability-indicating HPLC method for the determination of Riluzole hydrochloride in bulk and pharmaceutical dosage form has been reported. The separation was achieved on BDS Hypersil C18 column (100 × 4.6 mm i.d, 3μm) in isocratic elution mode with the mobile phase consisting of 5mM ammonium acetate and acetonitrile in the ratio of 50: 50 (v/v) and the column was maintained at 30°C. The detection of eluent from the column was detected using photo diode array detector (PDA) at 220nm and the flow rate was maintained at 1 ml/min. The proposed method has permitted the quantification in the linearity range of 50-400μg/ml. The method was validated in terms of accuracy, precision, linearity, limits of detection, limits of quantitation and robustness. The limit of detection and limit quantification were found to be 0.020μg/ml and 0.093μg/ml, respectively. This method has been successively applied to commercial tablet formulation and no interference from the tablet excipients was found. Riluzole hydrochloride was subjected to different stress conditions such as acid, base and neutral hydrolysis, oxidation, dry heat and photolytic stress conditions and the stressed samples were analyzed by the proposed method. As the proposed method could effectively separate the drug from its degradation products, it can be employed as stability-indicating method for the determination of these drugs in bulk and commercial products.