Stability indicating HPLC method for simultaneous determination of mephenesin and diclofenac diethylamine

Ks Jain,As Deshpande,Sv Londhe,Ms Phoujdar,Ps Mallade,Sv Mulgund,Ts Kulkarni

doi:10.4103/0250-474x.51950

Abstract

A simple, specific, accurate and stability-indicating reversed phase high performance liquid chromatographic method was developed for the simultaneous determination of mephenesin and diclofenac diethylamine, using a Spheri-5-RP-18 column and a mobile phase composed of methanol: water (70:30, v/v), pH 3.0 adjusted with o-phosphoric acid. The retention times of mephenesin and diclofenac diethylamine were found to be 3.9 min and 14.5 min, respectively. Linearity was established for mephenesin and diclofenac diethylamine in the range of 50-300 μg/ml and 10-60 μg/ml, respectively. The percentage recoveries of mephenesin and diclofenac diethylamine were found to be in the range of 99.06-100.60% and 98.95-99.98%, respectively. Both the drugs were subjected to acid, alkali and neutral hydrolysis, oxidation, dry heat, photolytic and UV degradation. The degradation studies indicated, mephenesin to be susceptible to neutral hydrolysis, while diclofenac diethylamine showed degradation in acid, H2O2, photolytic and in presence of UV radiation. The degradation products of diclofenac diethylamine in acidic and photolytic conditions were well resolved from the pure drug with significant differences in their retention time values. This method can be successfully employed for simultaneous quantitative analysis of mephenesin and diclofenac diethylamine in bulk drugs and formulations.

Highlights

Mephenesin (MEP), 3-(2-methylphenoxy)-1,2-propanediol, is a white crystalline powder, almost odorless, slightly soluble in water but freely soluble in alcohol, chloroform and solvent ether
This paper reports validated stability-indicating HPLC method for simultaneous determination of MEP and Diclofenac diethylamine (DDEA) in presence of their degradation products
The HPLC analysis was performed on reversed-phase high-performance liquid chromatographic system with isocratic elution mode using a mobile phase of methanol:water (70:30, v/v) pH 3.0 adjusted with ophosphoric acid on Spheri-5-RP-18 column (250×4.6 mm, 5 μm particle size) with 1 ml/min flow rate at 221 nm using UV detector

Summary

Introduction

Mephenesin (MEP), 3-(2-methylphenoxy)-1,2-propanediol (fig. 1), is a white crystalline powder, almost odorless, slightly soluble in water but freely soluble in alcohol, chloroform and solvent ether. This paper reports validated stability-indicating HPLC method for simultaneous determination of MEP and DDEA in presence of their degradation products.

Results

Conclusion