Development of RP-HPLC Method for Estimation of Indapamide and Amlodipine Besylate in Pharmaceutical Formulation

A simple, rapid, selective, precise and accurate RP-HPLC method for estimation of indapamide and amlodipine besylate was developed and validated as per ICH guidelines. Separation was carried out by using C18 (4.6 × 250 mm, 5μ) column and mobile phase was acetonitrile: buffer (0.05M ammonium acetate): triethylamine (65:35:0.3 v/v/v) pH 3, adjusted with dilute solution of 1% acetic acid. The analysis was performed by using UV-visible detector with pump SPD-20AD (LC-20A) at 238 nm with flow rate 1mL/min. The retention time for indapamide and amlodipine were found to be 5.71 min and 6.89 min, respectively. Linearity was observed in the concentration range of 1.5 to 30 μg/mL for indapamide with correlation coefficient (r²=0.9999) and 5 to 50 μg/mL for amlodipine besylate with correlation coefficient (r²=0.9996), respectively. The mean percent recoveries for indapamide and amlodipine besylate were found to be 99.80% and 99.97%, respectively. The ruggedness studies were carried out for different parameters i.e. different elapsed times (Interday, intraday) and different analysts. The proposed method can be successfully used for estimation of indapamide and amlodipine besylate as in bulk drug and pharmaceutical dosage form.