AIM: To determine the concentration of mycophenolic acid in human plasma by HPLC with
fluorescence detection. METHODS:
Using naproxen as internal standard, mycophenolic acid in plasma samples was determined by HPLC with protein precipitation. HPLC analytical column was created by Kromasil C 8 (150 mm ×4.6 mm, 5 μm). Separation was carried out at 25 °C. The mobile phase consisted of a mixture acetonitrile∶0.04 mol·L -1 glycine buffer, pH 9.2 ( 20∶80) pumped at a flow rate of 1.0 mL·min -1. A fluorescence detector was set at λ ex 342 nm, λ em 425 nm. RESULTS: The intrinsic impurity and the combination used drugs in plasma did not interfere with the
determination of the sample tests. There was good linear relationships(1/C weighted) between peak area ratio of mycophenolic acid to internal standard and C(r=0.999 9) within the range of 0.05- 40 mg·L -1. The precision of within-run and between-run was good. CONCLUTION: The method established in this paper can be used to determine the concentrations of mycophenolic acid in human plasma. Method can also be applied to the clinical pharmacy research in vivo.