Rapid colorimetric assay of diclofenac sodium tablets using 4-carboxyl-2,6-dinitrobenzene diazonium ion (CDNBD)

This study describes a novel simple, rapid and sensitive colorimetric assay method for diclofenac sodium tablets. The method is based on a simple aromatic ring derivatization technique using newly developed 4-carboxyl-2, 6-dinitrobenzenediazonium ion (CDNBD) as chromogenic derivatizing reagent with subsequent formation of an azo dye.