Development and Validation of Fast, Simple, Cost-effective and Robust RP-HPLC Method for Simultaneous Determination of Lisinopril and Amlodipine in Tablets

A new Reversed-Phase High-Performance Liquid Chromatography (RP-HPLC) method for simultaneous determination of lisinopril dihydrate and amlodipine besylate in tablets was developed and validated. This method operates under moderate chromatographic conditions, avoiding high column temperatures, ion-pair reagents, gradient elution or mobile phases with very low pH value as it is usually recommended by the majority of the existing RP-HPLC methods used for the same purpose. The developed method uses a C18 column, UV-detection and mobile phase consisting of methanol and phosphate buffer with pH 7.3. The method provides chromatograms with excellent peak symmetry and is very simple, selective, accurate, reproducible, robust and cost-effective. The rather moderate experimental conditions make the method favorable with regards to time, chemicals and consumables consumption and consequently very useful for application in the quality control laboratories in pharmaceutical companies. The method performance has been demonstrated using different reversed-phase columns and with different neutral mobile phases showing that it can be adjusted and used in different laboratories for analysis of different combinations of lisinopril with other antihypertensive active ingredients.