G.V.Adilakshmi

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.

A simple, accurate and stability indicating high performance liquid chromatographic (HPLC) method was developed for the simultaneous estimation of Torsemide and Spironolactone in combined dosage form. Isocratic RP-HPLC separation was achieved on Kromasil RP- C18 column (250mm×4.6mm; 5µm) using methanol: acetonitrile: water in the ratio of 50:30:20 (v/v), pH6.8, at flow rate of1.0ml/min at ambient temperature. Quantization was achieved by UV detection at 235nm over the concentration range of 10-60μg/ml for torsemide and 25-150μg/ml for spironolactone with percentage recoveries of range 99.688-101.792 and 98.282-101.811for torsemide and spironolactone respectively. Different stress degradation studies like acidic, alkaline, peroxide, thermal etc were measured for both standard drugs and results found that the stress degradation conditions doesn’t affect the elution of the both the drugs and hence the developed method was found to be stability indicating method.