Pharmaceutica Analytica Acta

Abstract

Intrinsic Stability Study of Armodafinil Hydrochloride by Forced Degradation and Impurity Profiling

Deepti Jain and Pawan K Basniwal

Objective: A novel RP-HPLC-DAD-HRMS method was developed for determination of armodafinil in presence of related substances viz. impurities and forced degradation products and its intrinsic stability was established by forced degradation profiling. Method: Armodafinil and its degradation products were successfully separated on Zorbax Eclipse Plus C18 column (250 × 4.6 mm, 5 μm) by mixture of 0.1% formic acid and acetonitrile (in gradient mode) at 1 ml/min flow rate within 20 min and detection was performed by photodiode-array detector at 252 nm. Results: Drug was extensively degraded in alkaline conditions followed by acidic and neutral conditions, while there was no degradation observed in thermal, oxidative and ultra-violet degradation conditions. Only one impurity (AMD-Imp) was identified as phenylmethanesulfinic acid. Structure of degradation products and degradation pathways of drug have been postulated for hydrolytic condition. Conclusion: Armodafinil was extensively degraded in basic condition followed by acidic and neutral condition. Four DPs vis. AMD3, AMD4, AMD5 and AMD6 were observed in all the conditions. No degradation was found in thermal, UV light and oxidative conditions