Department of Pharmacy, University of Oslo, P.O. Box 1068, Blindern, 0316 Oslo, Norway.
West China School of Public Health and West China Fourth Hospital, Sichuan University, Chengdu 610041, China.
Anal Chem. 2023 Jun 13;95(23):8982-8989. doi: 10.1021/acs.analchem.3c01052. Epub 2023 May 31.
For the first time, this paper introduces the idea of generic extraction conditions in electromembrane extraction (EME), where the selection of the liquid membrane is based on the charge () and hydrophobicity (log ) of the analyte. A broad range of organic solvents were tested as liquid membranes, and 90 basic pharmaceuticals were used as model analytes (-4.2 < log < 8.1). 2-Nitrophenyl octyl ether (NPOE) was confirmed as a highly efficient liquid membrane for mono- and dibases (+1.0 ≤ ≤ +2.0) of low polarity in the log range of 2.2-6.4. This log range was set as the extraction window (operational range) of NPOE. NPOE provided very high operational stability. At 50 V, the current was at a 1 μA level, and gas formation and drifting pH due to electrolysis were insignificant. 2-Undecanone was discovered as a new and robust alternative. This solvent extracted monobasic analytes ( = +1) in the log range of 1.0-5.8 and was efficient even for bases of moderate polarity. The current was at the 1-3 μA level when 2-undecanone was operated at 50 V. Tri(pentyl) phosphate emerged as another new alternative for bases in the log range of 0.5 to 5.5, providing greater selectivity differences. This solvent provided a higher current (30-50 μA), but the EME system stability was not compromised. 2-Undecanone and tri(pentyl) phosphate extracted protonated bases mainly by hydrogen bond interactions. NPOE, on the other hand, extracted based on a combination of hydrogen bond and π-type interactions and was consequently less selective.
本文首次提出了电迁移萃取（EME）中通用萃取条件的概念，该概念基于分析物的电荷（）和疏水性（log ）选择液膜。本文测试了广泛的有机溶剂作为液膜，并用 90 种基本药物作为模型分析物（-4.2 < log < 8.1）。2-硝基辛基醚（NPOE）被确认为一种高效的液膜，适用于极性较低的单碱基和二碱基（+1.0 ≤ ≤ +2.0），log 范围为 2.2-6.4。该 log 范围被设定为 NPOE 的萃取窗口（工作范围）。NPOE 提供了非常高的操作稳定性。在 50V 时，电流为 1μA 水平，由于电解产生的气体形成和漂移 pH 值可以忽略不计。2-十一酮被发现是一种新的、强大的替代品。该溶剂萃取了 log 范围为 1.0-5.8 的单碱基分析物（ = +1），即使对中等极性的碱基也具有高效性。当 2-十一酮在 50V 下运行时，电流在 1-3μA 水平。磷酸三戊酯（TPP）作为另一种新的替代物，适用于 log 范围为 0.5 至 5.5 的碱基，提供了更大的选择性差异。该溶剂提供了更高的电流（30-50μA），但不会影响 EME 系统的稳定性。2-十一酮和 TPP 主要通过氢键相互作用萃取质子化碱基。NPOE 则基于氢键和π型相互作用的组合来萃取碱基，因此选择性较低。
