Abstract

An innovative, sensitive, simple and rapid method has been developed for estimation of selective H1 receptor antagonist. The method is based on bromination of drug. The proposed spectrophotometric method was developed using potassium bromate-potassium bromide mixture in acidic condition followed by the reaction of surplus bromine with methyl orange dye and measure the absorbance at 506 nm. Beer’s law was obeyed in the concentration range of 0.2-1.2 μg/ml, 0.3-1.7 μg/ml and 0.03-0.18 μg/ml for olopatadine hydrochloride, fexofenadine hydrochloride and azelastine hydrochloride respectively. The method was optimized for concentration of hydrochloride, ml of hydrochloride, ml of potassium bromate-potassium bromide mixture, ml of dye and reaction time. Developed method has been validated in accordance to International Council on Harmonisation guideline Q2R1. Statistical analysis proved that the method is accurate, sensitive, selective, precise and reproducible. The simple procedure with high accuracy, wide linearity range and sensitivity imply that the demonstrated method to be appropriate for routine estimation and quality control assay of pharmaceutical formulations.