Spectrophotometric determination of Diclofenac Sodium in pure form and in the pharmaceutical preparations

Abstract

A rapid, simple and sensitive method for the determination of Diclofenac sodium using sodium 1,2-naphthoquine- 4-sulfonate (NQS) as reagent in an alkaline medium (pH 11.9) to form an orange-colored product that was a maximum absorbance at 456 nm. Beer’s law is obeyed in the range (8-44 µg/mL), with molar absorptivity (6.965×10³ L/mol.cm), correlation coefficient 0.9996, and the limit of detection (0.185 µg/mL). The method has been successfully applied to the determination of Diclofenac sodium in pharmaceutical preparations.