Siam Reema, Ali Abeer, Abu-Reziq Raed
Casali Center of Applied Chemistry, Institute of Chemistry, Center for Nanoscience and Nanotechnology, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel.
Polymers (Basel). 2024 Sep 26;16(19):2728. doi: 10.3390/polym16192728.
This article presents a method for producing chiral ionic liquid-based polyurea microcapsules that can be magnetically separated. The method involves entrapping hydrophilic magnetic nanoparticles within chiral polyurea microspheres. The synthetic process for creating these magnetic polyurea particles involves oil-in-oil (o/o) nano-emulsification of an ionic liquid-modified magnetite nanoparticle (MNPs-IL) and an ionic liquid-based diamine monomer, which comprises a chiral bis(mandelato)borate anion, in a nonpolar organic solvent, toluene, and contains a suitable surfactant. This is followed by an interfacial polycondensation reaction between the isocyanate monomer, polymethylenepolyphenyl isocyanate (PAPI 27), and the chiral diamine monomer, which generates chiral polyurea microcapsules containing magnetic nanoparticles within their cores. The microcapsules generated from the process are then utilized to selectively adsorb either the R or S enantiomer of tryptophan (Trp) from a racemic mixture that is dissolved in water, in order to evaluate their chiral recognition capabilities. During the experiments, the magnetically separable chiral poly(ionic liquid) microcapsules, which incorporated either the R or S isomer of chiral bis(mandelato)borate, exhibited exceptional enantioselective adsorption performance. Thus, the chiral polymeric microcapsules embedded with the R-isomer of the bis(mandelato)borate anion demonstrated significant selectivity for adsorbing L-Trp, yielding a mixture with 70% enantiomeric excess after 96 h. In contrast, microcapsules containing the S-isomer of the bis(mandelato)borate anion preferentially adsorbed D-Trp, achieving an enantiomeric excess of 73% after 48 h.
本文介绍了一种制备可磁分离的手性离子液体基聚脲微胶囊的方法。该方法包括将亲水性磁性纳米颗粒包裹在手性聚脲微球内。制备这些磁性聚脲颗粒的合成过程涉及在非极性有机溶剂甲苯中，将离子液体修饰的磁铁矿纳米颗粒（MNPs-IL）和一种基于离子液体的二胺单体（其包含手性双（扁桃酸根）硼酸根阴离子）进行油包油（o/o）纳米乳化，并含有合适的表面活性剂。随后，异氰酸酯单体多亚甲基多苯基异氰酸酯（PAPI 27）与手性二胺单体之间发生界面缩聚反应，生成核心含有磁性纳米颗粒的手性聚脲微胶囊。然后利用该过程生成的微胶囊从溶解于水中的外消旋混合物中选择性吸附色氨酸（Trp）的R或S对映体，以评估其手性识别能力。在实验过程中，掺入手性双（扁桃酸根）硼酸根的R或S异构体的可磁分离手性聚（离子液体）微胶囊表现出优异的对映体选择性吸附性能。因此，嵌入双（扁桃酸根）硼酸根阴离子R异构体的手性聚合物微胶囊对吸附L-Trp表现出显著的选择性，96小时后得到对映体过量为70%的混合物。相比之下，含有双（扁桃酸根）硼酸根阴离子S异构体的微胶囊优先吸附D-Trp，48小时后对映体过量达到73%。
