Chromatographic separation of piracetam and its metabolite in a mixture of microsomal preparations, followed by an MS/MS analysis

• In vitro & in vivo piracetam metabolism.
• Proposed metabolic pathway for piracetam.
• In vivo pharmacokinetics of metabolite.
• Metabolite identification and characterization using LC–MS/MS & validation.
• In silico metabolite prediction using MetaboExpert and correlated with in vitro and in vivo.

A rapid bioanalytical method was evaluated for the simultaneous determination of piracetam and its metabolite (M1) in human microsomal preparations by fast ultra-performance liquid chromatography/tandem mass spectrometry (UPLC–MS/MS). In addition, a validated method of M1 in rat plasma was developed and successfully applied on pharmacokinetic studies. The present study was carried out to determine the metabolic pathways of piracetam for phase I metabolism and used cytochrome P450 isoforms responsible for the piracetam metabolism in human liver microsomes (HLMs). While additional potential metabolites of piracetam were suggested by computer-modeling. The resulting 2-(2-oxopyrrolidin-1-yl) acetic acid was the sole metabolite detected after the microsomal treatment. The amide hydrolysis mainly underwent to form a metabolite i.e., 2-(2-oxopyrrolidin-1-yl) acetic acid (M1).

The metabolite of piracetam was generated by using human liver Microsomes (in vitro studies), characterized by UPLC–MS/MS and confirmed by in silico and in vivo studies.Figure optionsDownload as PowerPoint slide