Quantitative determination of clopidogrel active metabolite in human plasma by LC-MS/MS

J Pharm Biomed Anal. 2008 Dec 1;48(4):1219-24. doi: 10.1016/j.jpba.2008.08.020. Epub 2008 Aug 23.


A quantitative method for the determination of clopidogrel active metabolite (AM) in human plasma was developed and validated using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Clopidogrel AM contains a thiol group, thus requiring stabilization in biological samples. The alkylating reagent 2-bromo-3'-methoxyacetophenone was used to stabilize clopidogrel AM in blood. An analog of the derivatized clopidogrel AM was used as the internal standard (IS). The derivatized samples were subjected to solid-phase extraction with a C2 disk plate and the overall procedure exhibited good reaction (more than 90%) and recovery efficiencies (from 85% to 105%). The derivative of clopidogrel AM (MP-AM) and IS were separated on an ODS column and quantified by tandem mass spectrometry with electrospray ionization. No significant endogenous peaks corresponding to MP-AM or IS were detected in blank human plasma samples, and no significant matrix effect was observed for MP-AM and IS in human plasma samples (from 102% to 121%). The calibration curve ranged from 0.5 to 250 ng/mL with good linearity, and extended by validation of a 50-fold dilution. In the intra- and inter-assay reproducibility tests, the accuracy and precision were within 12% relative error and 6% coefficient of variation, respectively. The derivatized MP-AM was stable in human plasma for 4 months at -80 degrees C. The validated method was successfully used to analyze clinical samples and determine the pharmacokinetics of clopidogrel AM.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Area Under Curve
  • Calibration
  • Chromatography, Liquid / methods*
  • Clopidogrel
  • Drug Stability
  • Female
  • Freezing
  • Humans
  • Male
  • Metabolic Clearance Rate
  • Middle Aged
  • Molecular Structure
  • Platelet Aggregation Inhibitors / blood*
  • Platelet Aggregation Inhibitors / metabolism*
  • Platelet Aggregation Inhibitors / pharmacokinetics
  • Reference Standards
  • Reproducibility of Results
  • Solid Phase Extraction
  • Spectrometry, Mass, Electrospray Ionization
  • Tandem Mass Spectrometry / methods*
  • Ticlopidine / analogs & derivatives*
  • Ticlopidine / blood
  • Ticlopidine / metabolism
  • Ticlopidine / pharmacokinetics
  • Time Factors
  • Young Adult


  • Platelet Aggregation Inhibitors
  • Clopidogrel
  • Ticlopidine