Quantitative Determination of Amlodipine Besylate, Losartan Potassium, Valsartan and Atorvastatin Calcium by HPLC in their Pharmaceutical Formulations

Abstract

Amlodipine besylate is a calcium channel blocker which is used in treatment of hypertension alone or in combination with other antihypertensive drugs like angiotensin-II-receptor antagonists (ARA II) group (Losartan potassium and Valsartan) or in combination with anti hyperlipidemic agent like Atorvastatin calcium. RP- HPLC method was developed for the assay of these drugs. The method was performed by reversed phase high performance liquid chromatography using a mobile phase 0.01 M ammonium acetate buffer (pH 5.5): acetonitrile with detection at 240 nm on a spherical monomeric C18 column (250 mm × 4.6 mm, 5 μm) at flow rate of 1.5 ml/min. The proposed method was validated in terms of linearity ranged between [(2-12, 10-60, 16-96, 4-24 μg/ml) corresponding levels of 20-120% w/w of the nominal analytical concentration] with linear regression equations were [{y=64.627x – 3.6383 (r= 0.9998), y=75.385x – 8.3856 (r= 0.9997), y=64.492x – 25.981 (r= 0.9998), y=70.964x – 28.505 (r= 0.9998}], accuracy [100.18 ± 1.38, 100.79 ± 0.59, 100.45 ± 0.58 and 100.8 ± 1.69%], precision [99.29, 99.33, 99.30 and 99.30%], limits of detection [0.03, 0.18, 0.15, 0.007 μg/ml] and limits of quantitation [0.1, 0.54, 0.45, 0.024 μg/ml] for Amlodipine besylate, Losartan potassium, Valsartan and Atorvastatin calcium respectively. Method validation was developed following the recommendations for analytical method validation of International Conference on Harmonization (ICH) and Food and Drug Administration (FDA) organizations.