Isocratic RP-HPLC Method Development, Validation and Stability Indicating Studies for Simultaneous Determination of Escitalopram and Clonazepam In the Combined Dosage Form

A new rapid, sensitive and precise stability indicating HPLC method was developed on kromasil RP-C18 column (250mm X 4.6mm, 5µm), for the simultaneous analysis of Escitalopram and Clonazepam. Chromatographic separation was achieved at 229nm by using a mobile phase composed of methanol, acetonitrile and phosphate buffer (70: 28: 2, v/v). Retention time of escitalopram and clonazepam were found to be 2.67min and 3.46min respectively. Method validation was done as per the ICH guidelines. Good linearity was established in the concentration range of 50-300µg/ml and 2.5-15µg/ml by escitalopram and clonazepam respectively. Resolution of escitalopram and clonazepam was found to be 5.25. Percentage RSD of precision was found to be less than 2. The percentage assay of escitalopram and clonazepam in commercial formulation was found to be 99.18 and 99.22 respectively. Stability of the molecule was measured by inducing different stress conditions like acidic, basic, peroxide, thermal, light and UV light.