Development and Validation of a Stability-Indicating RP-HPLC Method for Simultaneous Quantification of Tolfenamic Acid and Moxifloxacin in Pharmaceutical Formulations

Research Article

Abstract

A rapid, precise, and accurate reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for the simultaneous determination of Tolfenamic acid and Moxifloxacin in pharmaceutical formulations. Chromatographic separation was achieved on an Agilent C18 column (250 mm × 4.6 mm, 5 μm) using methanol and 0.05% acetic acid (pH 4.2 adjusted with triethylamine) in the ratio of 30:70 v/v as mobile phase at a flow rate of 1.0 mL/min. Detection was carried out at 287 nm using a UV detector. The retention times for Tolfenamic acid and Moxifloxacin were 3.762 and 5.237 minutes, respectively. The method demonstrated linear response over concentration ranges of 7.5-37.5 μg/mL for Tolfenamic acid and 15-75 μg/mL for Moxifloxacin with correlation coefficients of 0.999 for both analytes. The developed method was validated according to ICH guidelines for specificity, linearity, accuracy, precision, robustness, and system suitability. The accuracy of the method was established through recovery studies, with mean recoveries ranging from 98.23% to 100.51% for Tolfenamic acid and 99.88% to 101.75% for Moxifloxacin. The relative standard deviation values for intra-day and inter-day precision studies were less than 2%. The method successfully resolved both drugs with good peak shapes and minimal tailing. The validated method can be successfully applied for the routine quality control analysis of Tolfenamic acid and Moxifloxacin in pharmaceutical formulations