A High-Throughput RP-UPLC Assay for Simultaneous Determination of Telmisartan and Azelnidipine in Pharmaceutical Formulations.

Telmisartan, an angiotensin II receptor blocker, and azelnidipine, a dihydropyridine calcium channel blocker, are often co-prescribed for the effective management of hypertension. The development of accurate and efficient analytical methods is crucial for ensuring the quality control of these combination formulations. This study presents a rapid and reliable reversed-phase ultra-performance liquid chromatography (RP-UPLC) assay for the simultaneous determination of telmisartan and azelnidipine in pharmaceutical formulations. Efficient chromatographic separation was achieved on an ACQUITY BEH C18 column (100 mm × 2.1 mm, 3 µm) using an isocratic mobile phase of pH 4.0 ammonium acetate buffer and acetonitrile (75:25% v/v) at a flow rate of 0.5 mL/min. Detection was performed at 260 nm, with telmisartan and azelnidipine eluting at 1.833 and 3.583 min, respectively. The method demonstrated good efficiency and minimal tailing (<1.5). Validation parameters, including accuracy, precision, linearity, specificity, and sensitivity, were determined according to International Council for Harmonisation guidelines. Calibration curves for both analytes exhibited excellent linearity (correlation coefficients > 0.999) over a concentration range of 50-150%. Recoveries from tablet dosage forms ranged from 98.0% to 102.0%, with assay values falling within the prescribed range. This validated that reversed-phase ultra-performance liquid chromatography assay offers a high-throughput approach suitable for routine quality control analysis of telmisartan and azelnidipine in pharmaceutical formulations.