Novel experimental design approach for development of high-performance liquid chromatography method with fluorescence detection for amlodipine and telmisartan in their dosage form

This study endeavors to investigate and authenticate a proposed more sensitive and selective high-performance liquid chromatography with a fluorescence detector technique for the assessment of a binary formulation of Amlodipine (ADP) and Telmisartan (TMS). Both analytes were chromatographically separated by an optimized solvent system comprising acetonitrile and phosphate buffer at pH 4 (58:42, v/v), using Discovery ® C18 reverse phase high-performance liquid chromatography column (150 mm). The fluorescence detector excitation and emission wavelengths were determined to be 240 and 440 nm, respectively. The experiment followed Plackett–Burman’s design to optimize chemigraphic experimental variables. To assess the linearity of the method, calibration curves were generated using 12.5–200 μg/mL for ADP and 0.5–10 μg/mL for TMS, with good correlation coefficients of r = 0.9980 and 0.9970, respectively. In addition, the limits of detection for ADP and TMS were 1.04 and 0.15 µg/mL, respectively, while the corresponding limits of quantification were 3.14 and 0.44 µg/mL. The accuracy of the technique was confirmed by high percentage recovery with low relative standard deviation for both within-day and between-day precision. The analysis of the two medications in their prescribed form (tablet) was executed, and the retrieval and relative standard deviation were computed, followed by the application of a t -test. The results of the tablet analysis indicated that the overall accuracy (mean ± relative standard deviation) of the method was 99.78% ± 0.90% for ADP and 100.99% ± 0.07% for TMS. Hence, the proposed high-performance liquid chromatography method can be utilized for regular quality control of binary formulations consisting of ADP and TMS.