Benzofurazan‐based fluorophore for the selective determination of flupentixol dihydrochloride: Application to content uniformity testing

One of the most commonly used drugs in treatment of schizophrenia is flupentixol dihydrochloride, therefore it is important to develop a simple, low cost and sensitive spectrofluorimetric method for the estimation of flupentixol dihydrochloride. The yellow fluorescent product that is generated from the nucleophilic substitution reaction of the free lone pair of the alcoholic hydroxyl group of the drug and 4‐chloro‐7‐nitrobenzofurazan (NBD‐Cl) in Mcllvaine buffer pH 7.0 was estimated at 510 nm (λ_ex 460 nm). The variables that affect the development of the reaction product were explored and optimized. The linear range of this method was 0.5–2.5 μg ml^?1 with a limit of quantitation equal to 0.29 μg ml^?1. Our method was successfully applied for the assurance of flupentixol in tablet form with average percentage recovery of 99.08 ± 1.01% without obstruction from the basic excipients exhibits. Furthermore, our strategy was extended to study the content uniformity testing of flupentixol in Fluaxnol^® tablets.