Shibukawa A, Sawada T, Nakao C, Izumi T, Nakagawa T
Faculty of Pharmaceutical Sciences, Kyoto University, Japan.
J Chromatogr A. 1995 Apr 21;697(1-2):337-43. doi: 10.1016/0021-9673(94)00929-4.
An on-line frontal analysis HPLC system was developed for the determination of the unbound concentration of troglitazone (CS-045), a new oral antidiabetic agent, in human serum albumin (HSA) solution and in human plasma. This system consists of a high-performance frontal analysis (HPFA) column, an extraction column, and an analytical column, which are connected via two switching valves. After the direct injection of the sample solution into the HPFA column, the drug was eluted as a zonal peak with a plateau region. The unbound drug concentration was determined as the drug concentration in the plateau. As low as 0.3 nM unbound CS-045 was determined with good reproducibility. It was found that CS-045 strongly binds with HSA, and the bound fraction in the 550 microM HSA solution was 99.93%, which was very close to that in human plasma (99.89%). The bound fractions were constant within the total drug concentration range of 1-10 microM in the HSA solution and 250 nM-10 microM in human plasma.
开发了一种在线前沿分析高效液相色谱系统，用于测定新型口服抗糖尿病药物曲格列酮（CS - 045）在人血清白蛋白（HSA）溶液和人血浆中的游离浓度。该系统由一根高效前沿分析（HPFA）柱、一根萃取柱和一根分析柱组成，它们通过两个切换阀相连。将样品溶液直接注入HPFA柱后，药物以带有平台区的带状峰形式洗脱。游离药物浓度被确定为平台区的药物浓度。测定出低至0.3 nM的游离CS - 045，重现性良好。发现CS - 045与HSA强烈结合，在550 μM HSA溶液中的结合分数为99.93%，与人血浆中的结合分数（99.89%）非常接近。在HSA溶液中总药物浓度范围为1 - 10 μM以及人血浆中总药物浓度范围为250 nM - 10 μM时，结合分数保持恒定。
