A new simple method for quantification of cilostazol and its active metabolite in human plasma by LC–MS/MS: Application to pharmacokinetics of cilostazol associated with CYP genotypes in healthy Chinese population

Abstract

A simple, sensitive, and fully automated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the simultaneous quantification of cilostazol (CIL) and its active metabolite, 3,4-dehydro cilostazol (CIL-M), in human plasma. Plasma samples were processed by protein precipitation in 2 mL 96-deep-well plates, and all liquid transfer steps were performed through robotic liquid handling workstation, enabling the whole procedure fast, compared to the reported methods. Separation of analytes was successfully achieved on a UPLC BEH C 18 column (2.1 Â 100 mm, 1.7 μm) with mobile phase A (5 mM ammonium formate containing 0.1% formic acid) and mobile phase B (methanol) at a flow rate of 0.30 mL min À1 . The total run time was 3.5 min per sample. Mass spectrometric detection was conducted by electrospray ion source in positive ion multiple reaction monitoring mode. Calibration curves were linear over the concentration range of 1.0-800 ngÁmL À1 for CIL and 0.05-400 ngÁmL À1 for CIL-M. The coefficient of variation for the assay's precision was 12.3%, and the accuracy was 88.8-99.8%. It was fully validated and successfully applied to assess the influence of CYP genotypes on the pharmacokinetics of CIL after oral administration of 50 mg tablet formulations of CIL to healthy Chinese volunteers. The results suggest that, in Chinese population, the genotype of CYP3A5 affects the plasma exposure of CIL.

Effect of Baicalein on the Pharmacokinetics of Cilostazol and Its Two Metabolites in Rat Plasma Using UPLC-MS/MS Method

“…LC-MS/MS method is gradually applied for the detection of CLZ and its metabolites along with mass spectrometry development. Two studies reported UPLC-MS/MS method to simultaneously detect CLZ and 3,4-CLZ in human plasma ( Bhatt et al, 2015 ; Shen et al, 2021 ). However, only one metabolite detection in human plasma resulted in the application of pharmacokinetic research under restrictions.…”