HPLC Determination of Mycophenolate Mofetil and Its Active Metabolite Mycophenolic Acid in Human Plasma

Objective:To establish a rapid and feasible HPLC method for the determination of mycophenolate mofetil (MMF) and its active metabolite mycophenolic acid(MPA) in human plasma.Methods:The plasma sample(0.2 mL) was deproteinized with 0.5 mL of acetonitrile and then analyzed on an μBondapak C_(18) (3.9 mm×300mm)col- umn with a 40 mmol·L~(-1) tetrabutyl ammonium bromide (TBA)-acetonitrile (65:35) mobile phase.The flow rate was 1.0 mL·min~(-1),the eluent was detected at 254 nm,the MMF and MPA concentration were obtained by internal standard method,carbamazepine was used as an internal standard.Results:Calibration curves were linear over a concentration range of 0.2-37.5μg·mL~(-1) for MMF,and 0.5-35.0μg·mL~(-1) for MPA.Average recoveries were 98.00%-101.0% for MMF,97.88%-101.8% for MPA.Within-day precision of determination were less than 6% for both MMF and MPA,between-day precision were less than 8%.Conclusion:This method is simple, quick,accurate and can be used for the monitoring of the plasma concentration of MPA routinely and for the study on the clinical pharmacokinetics of MMF.