Spectrophotometric determination of Diclofenac sodium in pharmaceutical tablets via oxidative coupling reaction with 2,4-dinitrophenyl hydrazine in the presence of potassium periodate


Anew, simple, rapid and accurate spectrophotometric method for determination of diclofenac sodium via oxidative coupling with the2,4-dintrophenylhydrazine reagent in presence of oxidizing agent potassium periodate in the alkaline medium and the oxidation time 5 minute to form a blue colored compound ,which dissolved in water and showed the highest intensity of absorption at λmax 600 nm. The method has been obeyed Beer's law in the concentration range 0.8-16 µg.ml-1,with molar absorptivity of 2.8692×104 L. mol-1.cm-1,Sandel Index value 0.0110 µg.cm-2, the detection limited 0.088106 µg.ml-1, with correlation coefficient 0.9975. The relative standard deviation of the method does not exceed 2.97%. The proposed method was applied successfully for the determination of diciofenac sodium in tablet by both the direct and standard addition methods for three concentrations, the recovery ranged between 97.3-99.9%.