Spectrophotometric assay of dipyrone in pharmaceutical preparations via oxidative coupling reaction with m-toluidine and potassium hexacyanoferrate (III)‎

الملخص EN

A simple, rapid and highly sensitive spectrophotometric method has been described for the determination of dipyrone in a bulk and in dosage forms.

The method depends on the organic oxidative coupling reaction of dipyrone with m-toluidine in the presence of potassium hexacyanoferrate (III) in aqueous solution to form purple product measured at 530 nm.

Beer’s law is obeyed in the concentration range 0.4-10.0 μ g.ml-1 with accuracy (average recovery) of 99.71% and precision (RSD) is less than 2%.

The molar absorptivity is 40770 l.mol-1.cm-1 with LOD 0.051 μ g.ml-1 and LOQ 0.167 μ g.ml-1.

The analytical results agree favourably with official method (iodimetric method) and also with certified values.