Spectrophotometric method for determination of Cefixime in its pure form and in pharmaceutical preparations using diazotization reaction and coupling with Chromotropic acid reagent

Abstract

A new study includes development of a swift, sensitive and Cheap spectrophotometric method to estimation of Cefixime as pure and in its dosage forms. In this method cefixime was displaced with an equivalent amount of sodium nitrite solution in acidic medium to form resultant diazonium salt that will be coupling with Chromotropic acid reagent in basic medium to yield an red azo dye that has maximum absorption at 514 nm versus its blank solution. Under optimum conditions, the concentration range obeyed Beer’s law is 0.5-20 μg/ml and the excellent determination coefficient was (R2= 0.9991) and molar absorptivity 2.36×104 l/mol.cm. .The detection limit (LOD) and quantification limit (LOQ) were found to be 0.322 and 0.748 μg/ ml, respectively. A relative error% was calculated and found in the range -2.75% to 4.02% , while the precision (RSD) was estimated as ≤ 1.36% .The stoichiometry of the resulting azo dye was found to be 1:1 Cefixime : Chromotropic acid . The proposed method was successfully applied to assay of Cefixime in tablets .