Abstract

STABILITY-INDICATING HPLC-DAD AND TLC-DENSITOMETRIC METHODS FOR DETERMINATION OF CROTAMITON IN THE PRESENCE OF ITS DEGRADATION PRODUCTS

Mohammed Wafaa Nassar, Khalid A.M. Attia, Ragab A. Said, Ahmed El-Olemy and Mohamed A. Hasan*

ABSTRACT

In the present work, a rapid, specific and reproducible reversed phase high performance liquid chromatography with diode array detection (HPLC-DAD) method has been developed and validated for the determination of crotamiton in the presence of its degradation products. The drug was found to be labile to acidic hydrolysis, alkaline hydrolysis, oxidation, photolysis, thermal and neutral hydrolytic conditions. The acidic hydrolysis gives the highest degradation percentage, so complete degradation of the drug was done using reflux with 1N HCl for 3 hours and the degradation pathway was confirmed using TLC, IR, 1H NMR and mass spectrometry. Then, thin-layer chromatography (TLC) - densitometry method has been developed and validated for determination of crotamiton in the presence of its acidinduced degradation product. The developed methods were validated according to the International Conference on Harmonization (ICH) guidelines demonstrating good accuracy and precision. The results were statistically compared with those obtained by the reported method, and no significant difference was found.

Keywords: Crotamiton; HPLC-DAD; TLC-densitometry and degradation product.