State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
School of Biological and Chemical Engineering, Yangzhou Polytechnic College, Yangzhou 225126, China.
Anal Chem. 2024 Nov 5;96(44):17665-17671. doi: 10.1021/acs.analchem.4c03716. Epub 2024 Oct 23.
The chiral recognition and separation of enantiomers are of great importance for biological research and the pharmaceutical industry. Preparing homochiral materials with adjustable size and chiral binding sites is beneficial for achieving an efficient chiral recognition performance. Here, a homochiral covalent organic framework membrane modified with β-cyclodextrin (CD-COF) was constructed, which was subsequently utilized as an electrochemical sensor for the enantioselective sensing of tryptophan (Trp) molecules. The preferential adsorption of l-Trp over d-Trp at the β-CD sites can enhance the surface charge density and hydrophilicity of the CD-COF membrane, resulting in an increased transmembrane ionic current. Trp enantiomers with concentrations down to 0.28 nM can be effectively discriminated. The l-/d-Trp recognition selectivity increases with the Trp concentration and reaches a value of 19.2 at 1 mM. The selective adsorption of l-Trp to the CD-COF membrane will also hinder its transport, resulting in a l-/d-Trp permeation selectivity of 15.3. This study offers a new strategy to construct homochiral porous membranes and achieve efficient chiral sensing and separation.
手性识别和对映体分离对于生物研究和制药工业具有重要意义。制备具有可调尺寸和手性结合位点的同手性材料有利于实现高效的手性识别性能。在这里，构建了一种用β-环糊精（CD）修饰的同手性共价有机骨架膜（COF），并将其用作电化学传感器，用于对色氨酸（Trp）分子进行对映选择性感应。β-CD 位对 l-Trp 的优先吸附作用增强了 CD-COF 膜的表面电荷密度和亲水性，从而增加了跨膜离子电流。可以有效区分浓度低至 0.28 nM 的 l-Trp 和 d-Trp。随着 Trp 浓度的增加，l-/d-Trp 的识别选择性增加，在 1 mM 时达到 19.2。l-Trp 对 CD-COF 膜的选择性吸附也会阻碍其传输，从而导致 l-/d-Trp 渗透选择性为 15.3。这项研究为构建同手性多孔膜和实现高效手性感应和分离提供了一种新策略。
