Karbwang J, Na-Bangchang K, Molunto P, Banmairuroi V, Congpuong K
Clinical Pharmacology Unit, Faculty of Tropical Medicine, Mahidol University, Pyathai, Bangkok, Thailand.
J Chromatogr B Biomed Sci Appl. 1997 Mar 7;690(1-2):259-65. doi: 10.1016/s0378-4347(96)00422-7.
A rapid, selective, sensitive and reproducible HPLC with reductive electrochemical detection for quantitative determination of artemether (ART) and its plasma metabolite, dihydroartemisinin (DHA: alpha and beta isomers) in plasma is described. The procedure involved the extraction of ART, DHA and the internal standard, artemisinin (ARN) with dichloromethane-tert.-methylbutyl ether (1:1, v/v) or n-butyl chloride-ethyl acetate (9:1, v/v). Chromatographic separation was performed with a mobile phase of acetonitrile-water (20:80, v/v) containing 0.1 M acetic acid pH 5.0, running through a microBondapak CN column. The method was capable of separating the two isomeric forms of DHA (alpha, beta). The retention times of alpha-DHA, beta-DHA, ARN and ART were 4.6, 5.9, 7.9 and 9.6 min, respectively. Validation of the assay method was performed using both extraction systems. The two extraction systems produced comparable recoveries of the various analytes. The average recoveries of ART, DHA and ARN over the concentration range 80-640 ng/ml were 86-93%. The coefficients of variation were below 10% for all three drugs (ART, alpha-DHA, ARN). The minimum detectable concentrations for ART and alpha-DHA in spiked plasma samples were 5 and 3 ng/ml, respectively. The method was found to be suitable for use in clinical pharmacokinetic study.
本文描述了一种采用还原电化学检测的快速、选择性、灵敏且可重现的高效液相色谱法，用于定量测定血浆中的蒿甲醚（ART）及其血浆代谢物二氢青蒿素（DHA：α和β异构体）。该方法包括用二氯甲烷 - 叔丁基甲基醚（1:1，v/v）或正丁基氯 - 乙酸乙酯（9:1，v/v）提取ART、DHA和内标青蒿素（ARN）。色谱分离采用含0.1 M乙酸（pH 5.0）的乙腈 - 水（20:80，v/v）流动相，通过微Bondapak CN柱进行。该方法能够分离DHA的两种异构体形式（α，β）。α - DHA、β - DHA、ARN和ART的保留时间分别为4.6、5.9、7.9和9.6分钟。使用两种提取系统对测定方法进行了验证。两种提取系统对各种分析物的回收率相当。在80 - 640 ng/ml浓度范围内，ART、DHA和ARN的平均回收率为86 - 93%。三种药物（ART、α - DHA、ARN）的变异系数均低于10%。加标血浆样品中ART和α - DHA的最低检测浓度分别为5和3 ng/ml。该方法适用于临床药代动力学研究。
