Reverse Phase Liquid Chromatography Method Development and Validation for Impurity Profiling of Donepezil Drug

Reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated for concurrent detection of five impurities in donepezil hydrochloride. Using the method employed an Hypersil ODS, 25 cm x 4.6 mm, 5.0µm), chosen for its superior retention, resolution, and reproducibility. The mobile phase was optimized to a gradient program consisting of solution A as 10 mM diammonium hydrogen orthophosphate in water (pH 6.0) and Solution B as acetonitrile and methanol (85:15v/v). This method demonstrated excellent peak symmetry, resolution, and reproducibility at wavelength of 230 nm and a column temperature at 35°C. Despite initial difficulties with peak shape, the final conditions produced reliable and high-quality chromatograms for impurity profiling. The RP-HPLC method effectively quantifies five impurities (Imp-A to Imp-E) and satisfies key validation criteria like accuracy, precision, linearity, specificity, and system suitability. It shows robust performance, though some impurities are challenging to detect at lower concentrations. System suitability tests confirm consistency in peak areas and retention times, validating the method as both reliable and cost-effective for impurity analysis in donepezil hydrochloride, ensuring the drug’s quality and safety.