Spectrophotometric estimation of dapsone in Schiff base in its pharmaceutical preparation using charge transfer complex method

The research included the development of a new and sensitive spectroscopic method for the estimation of dapsone in aqueous media, the method depends on the interaction of the Schiff base of the drug dapsone with the reagent 8-hydroxyquinoline in a basic medium and the additions were supplemented with distilled water to give a light yellow complex whose absorption intensity depends on the concentration of dapsone in the Schiff base and gives higher Absorbance at wavelength 350 nm, law limits were between 0.5-4.5 µg. ml−1 of dapsone, and molar absorbance was 6.257×103 L. mol−1. cm−1, the recovery rate is 100.1620%, and the relative standard deviation does not exceed 0.1430%, and the method was applied in the estimation of dapsone in its pharmaceutical formulation in the form of tablets.