Development of Indirect Spectrophotometric Method for the Estimation of Oxymetazoline Hydrochloride as Pure Formand in its Pharmaceutical Preparations

Abstract

This method involves the development of a highly sensitive spectrophotometric procedure for estimating oxymetazoline hydrochloride in pure form and pharmaceutical formulations. The method involved the oxidation of oxymetazoline hydrochloride with an excess amount of cerium sulfate (CeSO₄) in an acidic medium. The liberated cerium ion Ce(III) was then treated with arsenazo III reagent to form a colored complex with maximum absorption at 652 nm. The linearity of the standard calibration curve follows Beer's law in the concentration range of 1.25 to 12.5 μg/mL of oxymetazoline hydrochloride with a correlation coefficient of 0.9993 and molar absorptivity of 2.25×10⁴ L.mol^-1.cm^-1. The Sandell's sensitivity index was estimated and found to be 0.0147 μg/cm2. The limit of detection (LOD) and limit of quantitation (LOQ) were also calculated and found to be 0.3036 and 0.9824 μg/mL, respectively. The precision (RSD%) and the error percentage were also estimated and found to be in the ranges of ±0.446 to ±0.659 and -1.03% to 0.58%, respectively. The recommended procedure has been applied to estimate oxymetazoline hydrochloride in obtainable dosage forms (drops and sprays).