UPLC MS/MS method for quantification of mycophenolic acid and metabolites in human plasma: Application to pharmacokinetic study.

Background: We described the development and full validation of a rapid, high throughput sensible and accurate UPLC method using tandem mass spectrometry detection for mycophenolate acid (MPA) and its metabolites, MPA glucuronide (MPAG) and acyl MPA glucuronide (AcMPAG) concentration determination with MPA-D3 as internal standard in human plasma.

Methods: Plasma pretreatment involved a one-step protein precipitation with acetonitrile. The separation was performed by reverse-phase chromatography on a Waters BEH HSST3 100 mm*2.1 mm*1.8 μm column. The multiple reaction monitoring transitions used for quantification were m/z 321.04→303.02 for MPA, 524.09→303.02 for AcMPAG and MPAG and 324.03→306.04 for MPA-D3 in the electrospray positive ionization mode.

Results: The method was linear over the concentration range of 0.1-20mg/L for MPA and AcMPAG and 1-200mg/L for MPAG respectively. The intra- and inter-day precision values were below 14% and accuracy was from 94.0 to 103.3% at all quality control levels. The lower LOQ was 0.1 mg/L for MPA and AcMPAG, 1 mg/L for MPAG.

Conclusion: Sample analysis time was reduced to 7 min including sample preparation. The present method was successfully applied to a pharmacokinetic study following oral administration of enterocoated sodium mycophenolate in de novo renal transplantation.