Title: Development and Validation of a Stability-Indicating HPLC Method for Determination of Clorazepate Dipotassium and Its Main Impurities in Bulk Drug and Capsules
Abstract: A simple isocratic stability-indicating HPLC method was developed and validated for determination of clorazepate dipotassium in the presence of its main impurities; nordiazepam and 2-amino-5-chlorobenzophenone, in bulk drug and capsules.The chromatographic analysis was performed on a Zorbax Eclipse XDB-C18 column (75 mm x 4.6 mm i.d., 3.5 µm) using a mobile phase consisting of 5 mM ammonium formate in methanol and 5 mM ammonium formate in water (65: 35, v/v) at a flow rate of 0.7 mL/min and UV detection at 230 nm.The forced degradation studies were performed under various conditions according to the ICH guidelines.The degradation products from the studies were investigated by HPLC and, later, by tandem LC-MS.The validation tests including specificity, linearity, accuracy, precision, LOD and LOQ were performed.The calibration curves of the drug and the two related substances were linear in the concentration of 2 to 100 µg/mL (r 2 = 0.9990), 2-50 µg/mL (r 2 = 0.9995) and 0.4-25 µg/mL (r 2 = 0.9993), respectively.The proposed method was proven to be suitable for the quantitative determination and stability studies of clorazepate dipotassium in bulk drug and capsules.