Continuous micellar electrokinetic focusing of neutral species driven by ion concentration polarization
Continuous micellar electrokinetic focusing of neutral species driven by ion concentration polarization
复制标题
离子浓差极化驱动的中性物质的连续胶束电动聚焦
DOI：
10.1039/c9lc00327d
复制
发表时间：
2019
期刊：
影响因子：
6.1
通讯作者：
Anand, Robbyn K.
中科院分区：
文献类型：
--
作者：
Berzina, Beatrise;Anand, Robbyn K.
离子浓差极化（ICP）已广泛应用于完成带电物质的动电聚焦。然而，基于 ICP 的不带电（中性）化合物的提取和富集对于制药、生物和环境应用很重要，但尚未见报道。在这里，我们报告了基于 ICP 的连续萃取方法，通过将两种中性化合物分配到离子胶束相中，从水溶液中萃取两种中性化合物。我们的初步结果表明，萃取效率随着构成胶束相的表面活性剂的浓度而增加，达到98±2%，并且当目标化合物的浓度超过胶束的容量时急剧下降。作为与该方法的实际应用相关的一个关键特征，我们表明，通过表面活性剂的局部富集和组装成胶束，即使比临界胶束浓度低一个数量级，也会发生聚焦，从而最大限度地减少其消耗。为了强调这种方法与水净化的相关性，该方法被应用于芘的提取，芘是一种多芳烃模型。这种方法提供了在胶束电动色谱中开发的广泛选择性分离策略的途径。
Ion concentration polarization (ICP) has been broadly applied to accomplish electrokinetic focusing of charged species. However, ICP-based extraction and enrichment of uncharged (neutral) compounds, important for pharmaceutical, biological, and environmental applications, has not yet been reported. Here, we report the ICP-based continuous extraction of two neutral compounds from aqueous solution, by their partition into an ionic micellar phase. Our initial results show that the efficiency of the extraction increases with the concentration of the surfactant comprising the micellar phase, reaching 98 ± 2%, and drops precipitously when the concentration of the target compound exceeds the capacity of the micelles. As a key feature relevant to the practical application of this method, we show that focusing occurs even an order of magnitude below the critical micelle concentration through the local enrichment and assembly of surfactants into micelles, thus minimizing their consumption. To underscore the relevance of this approach to water purification, this method is applied to the extraction of pyrene, a model for polyaromatic hydrocarbons. This approach provides access to a broad range of strategies for selective separation that have been developed in micellar electrokinetic chromatography.