Zürcher G, Da Prada M
F. Hoffmann-La Roche Ltd., Pharmaceutical Research Department, Basel, Switzerland.
J Chromatogr. 1990 Sep 14;530(2):253-62. doi: 10.1016/s0378-4347(00)82329-4.
A reliable assay procedure for the determination of 3,4-dihydroxyphenyl-L-alanine (dopa) and its O-methylated metabolite 3-O-methyldopa (3-OMD) is described. Supernatants from deproteinized plasma samples were directly injected into a column-switching system, allowing on-line prepurification of the samples by cation-exchange chromatography followed by reversed-phase high-performance liquid chromatography with electrochemical detection. With this method, the detector response was linear from endogenous levels of dopa and 3-OMD up to microgram concentrations. This technique combines the simplicity of direct injection methods with advantages of procedures using a sample clean-up. It represents a valid tool for the rapid and accurate measurement of large numbers of plasma samples in animals treated with levodopa and in clinical trials with new levodopa formulations.
本文描述了一种可靠的测定3,4-二羟基苯-L-丙氨酸（多巴）及其O-甲基化代谢物3-O-甲基多巴（3-OMD）的分析方法。将脱蛋白血浆样品的上清液直接注入柱切换系统，通过阳离子交换色谱在线预纯化样品，然后进行反相高效液相色谱-电化学检测。用这种方法，检测器响应在多巴和3-OMD的内源性水平至微克浓度范围内呈线性。该技术将直接进样方法的简便性与使用样品净化程序的优点相结合。它是快速准确测量用左旋多巴治疗的动物和新左旋多巴制剂临床试验中大量血浆样品的有效工具。
