A rapid LC–ESI-MS/MS method for the quantitation of choline, an active metabolite of citicoline: Application to in vivo pharmacokinetic and bioequivalence study in Indian healthy male volunteers

A rapid, simple, and sensitive high performance liquid chromatography–tandem mass spectrometry method (LC–ESI-MS/MS) was developed and validated for the determination and pharmacokinetic investigation of choline (CL), active metabolite of citicoline in human plasma using metformin (MF) as IS. The chromatographic separation was performed on a reversed-phase Phenomenx Gemini C18 column with a mobile phase of methanol:water (containing 10 mM ammonium formate) (9:1, v/v). The calibration curves were linear over the range of 0.05–5 μg/ml. The validated LC–ESI-MS/MS method was successfully applied for the evaluation of pharmacokinetic parameters and bioequivalence study of test and reference control release (CR) tablet preparation of citicoline 1000 mg after a single oral administration to all 12 healthy male volunteers.