Química medicinal

Development and Validation of Spectrophotometric Methods for the Determination of Mesalazine in Pharmaceutical Formulation

Abstract

Fatima Altayib Alasha Abdalla and Abdalla Ahmed Elbashir

Two simple, accurate and precise spectrophotometric methods for the quantitative analysis of mesalazine (MSZ) in pharmaceutical formulation have been described. The first method (A) is based on the charge transfer reaction with alizarin red sulphonate (ARS) in the solution of pH 8.0 to form a violet product showing maximum absorbance at 600 nm. The second method (B) is a derivatisation method involving reaction of MSZ with 1,2-naphthoquinone-4- sulphonate (NQS) in alkaline medium at pH 12.0 to form an orange product exhibiting maximum absorbance at 470 nm. All variables affecting the reactions were studied and optimized. Beer's law was obeyed in the concentration ranges of 15-97.5 and 2-22 μg/mL for methods A and B, respectively. The molar absorptivity, Sandell sensitivity, detection and quantification limits were calculated. The two methods were successfully applied to the determination of MSZ in pharmaceutical formulation.