Baharfar Mahroo, Yamini Yadollah, Seidi Shahram, Karami Monireh
Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, P.O. Box: 14115-175, Tehran, Iran.
Department of Chemistry, Faculty of Sciences, Tarbiat Modares University, P.O. Box: 14115-175, Tehran, Iran.
J Chromatogr B Analyt Technol Biomed Life Sci. 2017 Nov 15;1068-1069:313-321. doi: 10.1016/j.jchromb.2017.10.062. Epub 2017 Nov 2.
In this work, a microfluidic device was developed for on-chip electromembrane extraction of trace amounts of ephedrine (EPH) and clonidine (CLO) in human urine and plasma samples followed by HPLC-UV analysis. Two polymethylmethacrylate plates were used as substrates and a microchannel was carved in each plate. The microchannel channel on the underneath plate provided the flow pass of the sample solution and the one on the upper plate dedicated to a compartment for the stagnant acceptor phase. A piece of polypropylene sheet was impregnated by an organic solvent and mounted between the two parts of the chip device. An electrical field, across the porous sheet, was created by two embedded platinum electrodes placed in the bottom of the channels which were connected to a power supply. The analytes were converted to their ionized form, passed through the supported liquid membrane, and then extracted into the acceptor phase by the applied voltage. All the effective parameters including the type of the SLM, the SLM composition, pH of donor and acceptor phases, and the quantity of the applied voltage were evaluated and optimized. Several organic solvents were evaluated as the SLM to assess the effect of SLM composition. Other parameters were optimized by a central composite design. Under the optimal conditions of voltage of 74V, flow rate of 28μLmin, 100 and 20mM HCl as acceptor and donor phase composition, respectively, the calibration curves were plotted for both analytes. The limits of detection were less than 7.0 and 11μgL in urine and plasma, respectively. The linear dynamic ranges were within the range of 10-450 and 25-500μgL (r˃0.9969) for CLO, and within the range of 20-450 and 30-500μgL (r˃0.9907) for EPH in urine and plasma, respectively. To examine the capability of the method, real biological samples were analyzed. The results represented a high accuracy in the quantitative analysis of the analytes with relative recoveries within the range of 94.6-105.2% and acceptable repeatability with relative standard deviations lower than 5.1%.
在本研究中，开发了一种微流控装置，用于对人尿液和血浆样本中的痕量麻黄碱（EPH）和可乐定（CLO）进行芯片上的电膜萃取，随后进行HPLC-UV分析。使用两块聚甲基丙烯酸甲酯板作为基底，在每块板上刻蚀出一个微通道。下面板上的微通道提供样品溶液的流动通道，上面板上的微通道专门作为静止接收相的隔室。一块聚丙烯片材用有机溶剂浸渍后安装在芯片装置的两部分之间。通过放置在通道底部并连接到电源的两个嵌入式铂电极，在多孔片材上产生电场。分析物转化为离子化形式，穿过支撑液膜，然后通过施加的电压萃取到接收相中。对包括支撑液膜类型、支撑液膜组成、供体和受体相的pH值以及施加电压量在内的所有有效参数进行了评估和优化。评估了几种有机溶剂作为支撑液膜，以评估支撑液膜组成的影响。通过中心复合设计对其他参数进行了优化。在74V电压、28μLmin流速、分别为100和20mM HCl的接收相和供体相组成的最佳条件下，绘制了两种分析物的校准曲线。尿液和血浆中的检测限分别小于7.0和11μgL。可乐定在尿液和血浆中的线性动态范围分别为10-450和25-500μgL（r˃0.9969），麻黄碱在尿液和血浆中的线性动态范围分别为20-450和30-500μgL（r˃0.9907）。为了检验该方法的能力，对实际生物样品进行了分析。结果表明，该方法在分析物的定量分析中具有很高的准确性，相对回收率在94.6-105.2%范围内，具有可接受的重复性，相对标准偏差低于5.1%。
