Flow injection analysis of oxymetazoline hydrochloride with inhibited chemiluminescent detection

A rapid and sensitive chemiluminescence method for the quantitation of oxymetazoline hydrochloride in pharmaceutical formulations has been developed. Oxymetazoline hydrochloride inhibits strongly the chemiluminescence from the oxidation of luminol in alkaline medium. Based on this effect, a simple method is proposed for the determination of this imidazoline derivative by flow injection analysis employing chemiluminescence detection. The optimization of the experimental and instrumental variables such as, selection of the oxidant, concentration of reagents, flow rates, injection volume, etc., has been carried out using the proposed flow injection manifold. The performance characteristics have been established, showing a wide linear response in the range of 1.88–200 ng/ml and a detection limit of 1.21 ng/ml. This is the first chemiluminescent method for the determination of oxymetazoline which has been satisfactorily applied to the analysis of the drug in intranasal pharmaceutical formulations.