Analytical method for simultaneous estimation of amlodipine and hydrochlorothiazide in pharmaceutical dosage forms by RP-HPLC

Abstract

A new, simple, precise, accurate and reproducible RP-HPLC method for Simultaneous estimation of Amlodipine and Hydrochlorothiazide in bulk and pharmaceutical formulations. Separation of Amlodipine and Hydrochlorothiazide was successfully achieved on a Phenomenex Luna C18 (4.6×250mm, 5µm) particle size or equivalent in an isocratic mode utilizing Acetonitrile: Phosphate Buffer (pH-4.6) (45:55 v/v) at a flow rate of 1.0mL/min and elutes was monitored at 245nm, with a retention time of 2.102 and 3.537 minutes for Amlodipine and Hydrochlorothiazide respectively. The method was validated and the response was found to be linear in the drug concentration range of 6µg/mL to 14µg/mL for Amlodipine and 18µg/mL to 42µg/mL for Hydrochlorothiazide. The values of the slope and the correlation coefficient were found to be 77824 and 0.999 for Amlodipine and 10515 and 0.999 for Hydrochlorothiazide respectively. The LOD and LOQ for Amlodipine were found to be 0.6µg/mL and 1.8µg/mL respectively. The LOD and LOQ for Hydrochlorothiazide were found to be 0.8 µg/mL and 2.4µg/mL respectively. This method was found to be good percentage recovery for Amlodipine and Hydrochlorothiazide were found to be 100.351 and 100.93 respectively indicates that the proposed method is highly accurate. The specificity of the method shows good correlation between retention times of standard with the sample so, the method specifically determines the analytes in the sample without interference from excipients of tablet dosage forms. The method was extensively validated according to ICH guidelines for Linearity, Range, Accuracy, Precision, Specificity and Robustness.