Department of Pharmacy, University of Oslo, Oslo, Norway.
Department of Pharmacy, Faculty of Health and Medical Sciences, University of Copenhagen, Copenhagen, Denmark.
J Sep Sci. 2021 Jul;44(13):2631-2641. doi: 10.1002/jssc.202100167. Epub 2021 May 22.
In the present fundamental study, selectivity and efficiency of electromembrane extraction of 50 polar basic substances (-6.7 < log P < +1.0) was systematically studied for ten different supported liquid membranes. For each model substance, 23 molecular descriptors were collected and these were investigated as potential parameters for understanding of extraction efficiency and selectivity by means of partial least squares regression. Overall, a highly aromatic deep eutectic solvent composed of coumarin and thymol with addition of 2% ionic carrier (di(2-ethylhexyl) phosphate) provided the highest extraction efficiency with an average extraction yield of 69% from pure water samples, 55% from plasma, and 62% from urine. With this solvent system, ionic, cation-π, and π-π interactions between the supported liquid membrane and analytes were dominant. Supported liquid membranes without aromaticity, however, operated primarily based on hydrogen-bonding interactions. This is the first time the relationship between analyte properties, solvent composition, and extraction yield has systematically been studied for polar bases in electromembrane extraction. This new knowledge represents a first step toward enabling future development and optimization of electromembrane extraction systems for polar bases based on rational design, rather than trial-and-error approaches.
在本基础研究中，我们系统地研究了十种不同支撑液膜对 50 种极性碱性物质（-6.7<log P<+1.0）的电膜萃取的选择性和效率。对于每种模型物质，我们收集了 23 个分子描述符，并通过偏最小二乘回归研究这些描述符作为理解萃取效率和选择性的潜在参数。总的来说，由香豆素和百里酚组成的高度芳香性深共晶溶剂，并添加 2%的离子载体（二(2-乙基己基)磷酸酯），从纯水样品中提供了最高的萃取效率，平均萃取率为 69%，从血浆中为 55%，从尿液中为 62%。在这个溶剂体系中，支撑液膜和分析物之间存在离子、阳离子-π 和 π-π 相互作用。然而，没有芳香性的支撑液膜主要基于氢键相互作用。这是首次系统地研究电膜萃取中极性碱的分析物性质、溶剂组成和萃取产率之间的关系。这一新知识是基于合理设计而不是试错方法，为未来开发和优化极性碱的电膜萃取系统奠定了基础。
