Analytical method development and validation for estimation of clonazepam and brexpiprazole in bulk and tablet dosage form by rp-hplc

Abstract

This study presents the development and validation of a High-Performance Liquid Chromatographic (HPLC) method for the simultaneous estimation of Clonidine and Hydrochlorothiazide in both bulk and tablet dosage forms. Chromatographic separation was achieved using a Phenomenex Gemini C18 column with a mobile phase consisting of Methanol (80:20, v/v) at a flow rate of 1.0 ml/min. Detection of the analytes was performed at 230 nm, with retention times of 2.090 min for Clonidine and 3.289 min for Hydrochlorothiazide. Calibration curves exhibited linearity over the concentration ranges of 20 μg/ml for Clonidine and 25 μg/ml for Hydrochlorothiazide. The method was meticulously validated following ICH guidelines, encompassing assessments of specificity, accuracy, precision, linearity and range, ruggedness, robustness, and system suitability. The results demonstrated that the developed HPLC method is accurate, precise, and reproducible for the simultaneous quantification of Clonidine and Hydrochlorothiazide in pharmaceutical formulations. Importantly, the method exhibited high specificity, with no interference observed from tablet excipients or endogenous substances. Overall, the validated HPLC method offers a straightforward and rapid analytical approach suitable for routine quality control analysis in pharmaceutical laboratories. Its robust performance, confirmed through validation parameters including accuracy, precision (with RSD values meeting acceptable criteria), and linearity, supports its practical utility in ensuring the quality and consistency of Clonidine and Hydrochlorothiazide formulations during manufacturing and quality assurance processes.