Simultaneous estimation of Losartan and Atenolol by RPHigh Performance Liquid Chromatography

Losar-beta is available for the treatment of hypertension. It contains losartan potassium(LS; 50mg) and atenolol (AT; 50mg). In the present study, simple, rapid, precise and accurate methods for the simultaneous estimation of these drugs have been developed and validated by HPLC. The method was validated with respect to its linearity, limit of quantitation (LOQ), limit of detection (LOD), precision, accuracy and robustness. HPLC was carried out with C-18 ODS column having 5?m, 250mm×4.60mm specifications along with a UV detector (235nm). The mobile phase used was acetonitrile: water: methanol (60:30:10 ) at a flow rate of 1ml/minute. Linearity was established by least square linear regression analysis and it was found to be linear over the concentration range of 5-50 ?g/mL for LS and AT. LOQ was found to be 0.071 ?g/mL for LS and 0.98 ?g/ml for AT. The LOD was 0.002 ?g/mL and 0.032 for LS and AT respectively. In precision studies, the % RSD was found to be 0.212 and 0.094 for LS and AT respectively. Percentage recovery was found to be 99.32 ± 0.23 for LS and 99.34± 0.28 for AT.