Spectrophotometric Determination of Sulfathiazole in Different Pharmaceutical Formulations

Abstract

A simple, rapid and sensitive spectrophotometric method for the determination of sulfathiazole in aqueous solution is described. The method is based on the diazotized coupling reaction of aniline with sulfathiazole drugs. A mixture of an acidic solution (hydrochloric acid) of the sulfathiazole and the chromogenic was treated with sodium nitrite and aniline to form an intense orange water-soluble dye that is stable and has a maximum absorption at 480 nm. It was observed that the method is applicable for the determination of sulfathiazole in Nicotrim, Contri, Biotran and Bactrim forte formulations. The LOD ( limit of detection) and LOQ ( limit of quantification) for the method were calculated and found to be 0.23 and 0.48 ppm respectively.