Department of Pharmacy, University of Oslo, P.O. Box 1068, Blindern, 0316, Oslo, Norway.
Department of Physics, University of Oslo, P.O. Box 1048, Blindern, 0316, Oslo, Norway.
Anal Chim Acta. 2020 Apr 1;1104:1-9. doi: 10.1016/j.aca.2020.01.058. Epub 2020 Jan 28.
Electromembrane extraction (EME) in small, stagnant and chip-like devices has the potential for future in-field operation. Literature briefly discuss such systems, but performance suffered from evaporative losses of sample and acceptor. To address this, the current paper reports electromembrane extraction (EME) of five basic drugs (model analytes) from aqueous buffer solutions and whole blood samples under stagnant conditions in a completely closed system. A laboratory-made polyoxymethylene (POM) well plate served as compartment for the sample solution, while a commercially available well filter plate was used to immobilize 2-nitrophenyl octyl ether (NPOE) as supported liquid membrane (SLM) and as closed compartment for the acceptor solution. Major design parameters (sample compartment and electrode geometry) and operational parameters (sample volume, voltage and extraction time) were investigated and optimized. Electrode geometry was not very critical, but extraction efficiency increased with decreasing sample volume. Extraction from 50 μL aqueous buffer solution for 60 min and with a voltage of 75 V was considered exhaustive (sample was depleted), with recoveries ranging between 75% and 87% for loperamide, haloperidol, methadone, nortriptyline, and pethidine (RSD: 2-12%). Extraction from whole blood samples under optimized conditions yielded slightly lower recoveries, ranging between 57 and 96% (RSD: 3-12%). Stagnant EME was evaluated in combination with liquid chromatography-mass spectrometry (LC-MS) as a highly specific instrumental method, and provided evaluation data on methadone from blood samples in accordance with regulatory requirements (LOD: 0.4 ng/mL, LOQ: 1.4 ng/mL, RSD: 6-20%). This work has improved upon the design of stagnant EME, moving it further towards a viable in-field operation device.
电膜萃取（EME）在小型、静止和芯片状设备中具有未来现场操作的潜力。文献简要讨论了此类系统，但由于样品和接受体的蒸发损失，性能受到了影响。为了解决这个问题，本论文报告了在完全封闭系统中，在静止条件下，从水溶液缓冲液和全血样品中电膜萃取（EME）五种基本药物（模型分析物）。一个实验室制造的聚甲醛（POM）井板用作样品溶液的隔室，而一个市售的井过滤器板用于固定 2-硝基苯基辛基醚（NPOE）作为支撑液膜（SLM）和接受溶液的封闭隔室。主要设计参数（样品隔室和电极几何形状）和操作参数（样品体积、电压和萃取时间）进行了研究和优化。电极几何形状不是很关键，但萃取效率随样品体积的减少而增加。从 50 μL 水溶液缓冲液中萃取 60 分钟，并施加 75 V 的电压被认为是完全萃取（样品耗尽），洛哌丁胺、氟哌啶醇、美沙酮、去甲替林和哌替啶的回收率在 75%至 87%之间（RSD：2-12%）。在优化条件下从全血样品中萃取，回收率略低，范围在 57%至 96%之间（RSD：3-12%）。静止 EME 与液相色谱-质谱联用（LC-MS）相结合作为一种高度特异的仪器方法进行了评估，并根据监管要求提供了血样中美沙酮的评估数据（LOD：0.4ng/mL，LOQ：1.4ng/mL，RSD：6-20%）。这项工作改进了静止 EME 的设计，使其更接近于可行的现场操作设备。
