LC-PDA and LC-MS Studies of Donepezil Hydrochloride Degradation Behaviour in Forced Stress Conditions

The aim of this work was to study the intrinsic stability of donepezil hydrochloride in conditions of forced degradation (acid stress, alkaline stress, oxidant stress, light exposure and dry heat). The degradation profile of donepezil was characterized by liquid chromatography-mass spectrometry (LC-MS) and high-performance liquid chromatography coupled with photodiode array detection (LC-PDA). According to the results, the degradation products were separated and detected in acid and alkaline solutions. After seven days at room temperature, the recovery of donepezil in alkaline solution (0.1 mol L-1 NaOH) was about 42%, and three degradation products were detected. In acid solution (0.1 mol L-1 HCl), the drug recovery was about 86%, and three degradation products were detected. Thus, it was possible to propose a rapid and selective stability-indicating assay method using reversed-phase liquid chromatography for analysis of donepezil and their degradation products.