ఫార్మాస్యూటికా అనలిటికా ఆక్టా

నైరూప్య

Stability Indicating HPLC Method for Simultaneous Determination of Several Angiotensin-II-Receptor Antagonists in Their Dosage Forms

Abdullah A Elshanawane, Lobna M Abdelaziz and Hani M Hafez

A stability-indicating reversed-phase liquid chromatographic (RP-HPLC) method has been established for simultaneous determination of four angiotensin-II-receptor antagonists (Losartan potassium, Valsartan, Telmisartan and Irbesartan) in the presence of the degradation products generated in studies of forced decomposition. All drug substances were subjected to drastic condition of stress studies involving hydrolysis by acid and base, thermal decomposition by heat at 70°C, oxidation by hydrogen peroxide and photo degradation. Losartan potassium and Valsartan were degraded acidic conditions. Irbesartan was degraded basic conditions. Telmisartan showed good stability against all stress conditions. Successful separation of the drugs from the degradation products was achieved on ACE C18 column (250 mm×4.6 mm, 5 μm) with 65:35 % (v/v) potassium dihydrogen phosphate (0.025 M, pH 6.0): acetonitrile as a mobile phase at flow rate 1.5 ml/min with UV detection at 220 nm. The proposed method was validated in terms of linearity, accuracy, precision and limits of detection and quantitation. Statistical analysis proved the method enabled reproducible and selective quantification of these drugs as the bulk drug and in pharmaceutical dosage forms. Because the method effectively separates the drugs from their degradation products, it can be used as stability-indicating.