Validated Reverse Phase HPLC Method for the Determination of Impurities in Etoricoxib

Abstract

This paper describes the development of reverse phase HPLC method for etoricoxib in the presence of impurities and degradation products generated from the forced degradation studies. The drug substance was subjected to stress conditions of hydrolysis, oxidation, photolysis and thermal degradation. The degradation of etoricoxib was observed under base and oxidation environment. The drug was found stable in other stress conditions studied. Successful separation of the drug from the process related impurities and degradation products were achieved on zorbax SB CN (250 x 4.6 mm) 5 μm particle size column using reverse phase HPLC method. The isocratic method employed with a mixture of buffer and acetonitrile in a ratio of 60:40 respectively. Disodium hydrogen orthophosphate (0.02 M) is used as buffer and pH adjusted to 7.20 with 1 N sodium hydroxide solution. The HPLC method was developed and validated with respect to linearity, accuracy, precision, specificity and ruggedness.