Spectrophotometric Determination of Mefenamic Acid in Pharmaceutical Preparations Via Arsenazo III – Cerium (III) Reaction*

Lena S.Awadis,Nabeel S Othman

doi:10.33899/rjs.2009.40249

Abstract

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 g mefenamic acid in a final volume of 25 ml. The proposed method has been applied successfully to determine mefenamic acid in pharmaceutical preparations.

Highlights

Mefenamic acid [2-(2,3-dimethyl phenyl)amino]benzoic[I] acid is a non-steroidal anti-inflammatory drug which has analgesic, anti-inflammatory and antipyretic actions
Different techniques have been described for the determination of mefenamic acid: High performance liquid chromatography has been used for the determination of the drug in biological fluids such as human plasma (Niopas and Mamzoridi, 1994) or in human serum (Mohammed et al, 2004), and in horse plasma (Ishidaka et al, 1986)
Flow- injection technique was used in the determination of mefenamic acid, the methods based on formation of complex with Al(III) (Albero et al, 1995), tris (2, 2 bipyridyl) ruthenium (III) (Fatma et al, 2000)

Summary

Introduction

Mefenamic acid [2-(2,3-dimethyl phenyl)amino]benzoic[I] acid is a non-steroidal anti-inflammatory drug which has analgesic, anti-inflammatory and antipyretic actions. It is used specially in the treatment of rheumatoid arthritis, osteoarthritis and other muscular-skeletal diseases (Martindale, 1982). Terbium sensitized fluorescence is used to develop a sensitive spectrofluorometric method for determination of mefenamic acid (Pinclopi et al, 1998), another spectrofluorimetric method based on oxidation of mefenamic acid with cerium (IV) (Tabrizi, 2006 ). Flow- injection technique was used in the determination of mefenamic acid, the methods based on formation of complex with Al(III) (Albero et al, 1995), tris (2, , 2 bipyridyl) ruthenium (III) (Fatma et al, 2000) Different techniques have been described for the determination of mefenamic acid: High performance liquid chromatography has been used for the determination of the drug in biological fluids such as human plasma (Niopas and Mamzoridi, 1994) or in human serum (Mohammed et al, 2004), and in horse plasma (Ishidaka et al, 1986).

Methods

Results

Conclusion