Zeng L, Nath C E, Shaw P J, Earl J W, McLachlan A J
Faculty of Pharmacy, University of Sydney, NSW 2006, Australia.
Biomed Chromatogr. 2009 Jan;23(1):92-100. doi: 10.1002/bmc.1088.
A simple, accurate and sensitive HPLC method was developed for measuring total and unbound mycophenolic acid (MPA) in human plasma. Total MPA was extracted by protein precipitation and ultrafiltration was used to assess unbound MPA concentrations. The supernatant (20 microL) or ultrafiltrate (100 microL) was injected onto a C(18) HPLC column with a mobile phase of 0.05 m sodium phosphate buffer (pH 2.31)-acetonitrile (55:45, v/v for total MPA; 50:50 for unbound MPA) with UV detection at 254 nm. The extraction recovery was over 93% and reproducible. The assay was linear over the concentration range of 0.07-50 mg/L for total MPA and 4-1500 microg/L for unbound MPA. Intra- and inter-day assay reproducibility was less than 10%. Detection limits were 0.04 mg/L and 2 microg/L for total and unbound MPA, respectively. The assay utility was established in samples collected from five paediatric bone marrow transplant recipients who were receiving intravenous doses of mycophenolate mofetil. In these patients MPA concentrations ranged from 0.07 to 7.83 mg/L and unbound drug concentrations ranged from 2.1 to 107.5 microg/L. This method can be effectively applied to MPA pharmacokinetics in paediatric patients.
建立了一种简单、准确且灵敏的高效液相色谱法（HPLC），用于测定人血浆中总霉酚酸（MPA）和游离霉酚酸的含量。总MPA通过蛋白沉淀法提取，超滤法用于评估游离MPA的浓度。取20微升上清液或100微升超滤液注入C(18)高效液相色谱柱，流动相为0.05 m磷酸钠缓冲液（pH 2.31）-乙腈（总MPA为55:45，v/v；游离MPA为50:50），于254 nm处进行紫外检测。提取回收率超过93%且具有可重复性。该测定法在总MPA浓度范围为0.07 - 50 mg/L和游离MPA浓度范围为4 - 1500 μg/L内呈线性。日内和日间测定的重现性小于10%。总MPA和游离MPA的检测限分别为0.04 mg/L和2 μg/L。该测定法在从五名接受静脉注射霉酚酸酯的儿科骨髓移植受者采集的样本中得到了验证。在这些患者中，MPA浓度范围为0.07至7.83 mg/L，游离药物浓度范围为2.1至107.5 μg/L。该方法可有效应用于儿科患者的MPA药代动力学研究。
