Spectrophotometric determination of mefenamic acid in pharmaceutical preparations via arsenazo III-cerium (III)‎ reaction

Abstract EN

A sensitive indirect spectrophotometric method is proposed for determining mefenamic acid in pure form and in its pharmaceutical preparations.

The method is based on oxidation-reduction reaction between mefenamic acid and cerium (IV) ion, and subsequent Ce (III) reaction with arsenazo (III) reagent in acidic medium to produce a greenish-blue complex which is stable, water soluble and has a maximum absorption at 654 nm with a molar absorptivity of 1.731 × 105 l.mol-1.cm-1.

Beer’s law is obeyed in the concentration range from 1 to 10 μg mefenamic acid in a final volume of 25 ml.

The proposed method has been applied successfully to determine mefenamic acid in pharmaceutical preparations.