Evaluation of stability and simultaneous determination of fimasartan and amlodipine by a HPLC method in combination tablets

A simple, rapid, accurate, precise and robust HPLC method was developed for the simultaneous determination of fimasartan and amlodipine in tablet dosage form. Furthermore, stability of active ingredients was evaluated under normal and stress conditions. The isocratic elution was accomplished by Nucleosil C18 column (250 mm × 4.6 mm, 5 μm) at 40 °C. The mobile phase consisted of acetonitrile and 0.02 M monopotassium phosphate buffer (pH 2.2) in the ratio of 50:50 (v/v) was eluted at 1.0 ml/min. The eluent was monitored by the UV detector for fimasartan and amlodipine at 237 nm for 8 min, detection time. The validation of HPLC method was carried out in accordance with the ICH guidelines.