Innovative spectrophotometric method for accurate assay of Lercanidipine hydrochloride in the tablet and biological fluids: Utilizing azo coupling with N-NED reagent

Lercanidipine hydrochloride is a critical antihypertensive medication belonging to the dihydropyridine class of calcium channel blockers, known for its effectiveness in relaxing and dilating blood vessels, thereby enhancing circulation and reducing blood pressure. This study addresses the need for a sensitive and precise analytical method for estimating lercanidipine hydrochloride in bulk, pharmaceutical formulations, and biological fluids. Traditional analytical techniques have limitations, while azo coupling reactions, particularly with the reagent NED (N-(1-naphthyl) ethylenediamine), have proven effective due to their ability to produce quantifiable colored compounds. We present a novel spectrophotometric method that utilizes azo coupling with NED to estimate lercanidipine hydrochloride. The method adheres to Beer’s law within a concentration range of 1 to 30 μg/mL, exhibiting a molar absorptivity of 2.7289×10⁴ L/ mol.cm. Key findings include limits of detection (LOD) and quantification (LOQ) of 0.0683 μg/mL and 0.2275 μg/mL, respectively, demonstrating robust analytical performance. The method’s linearity and precision were validated, with Sandell’s sensitivity measured at 0.02375 μg/cm². The relative standard deviation for five replicates ranged from 0.43% to 2.24%, and precision was maintained between 96.53% and 102.13% without interference from common excipients. Statistical analysis using t-test and F-test at a 95% confidence level confirmed no significant variance between the proposed method and reference methods. This research highlights a valuable tool for accurate lercanidipine hydrochloride measurement, supporting improved therapeutic outcomes.