Development and Validation of Specific Stability Indicating CE Assay Method for HIV-Protease Inhibitor Indinavir Sulphate

Abstract

A capillary electrophoresis method has been optimized for the specific and stability indicating assay for indinavir sulphate, a HIV-protease inhibitor. The stress-degraded studies showed that the drug is susceptible to degrade in acidic, alkaline and neutral hydrolysis; and also in oxidation and thermal conditions. The separation of indinavir sulphate and their degradation products were tested under different electrophoretic conditions and finally, 25 mM phosphate buffer (pH 3.0) were optimized. The detection was performed at a UV wavelength of 196 nm. In the previously reported CE method for assay of indinavir sulphate, diazepam is used as an internal standard, which is susceptible to degrade under acidic pH condition. In this proposed method, imidazole has been used as an IS and is stable over acidic pH condition used in this experiment. The proposed CE method is also superior over the reported TLC method in terms of simplicity, cost and resolving the number of degradation products. The method was also validated and the recoveries of active ingredients in bulk drugs and formulations are greater than 99.55% with an RSD ≤1.23%. This is the first report on an ideal stability-indicating CE method that quantifies selectively indinavir sulphate in the presence of degradation products.