A general strategy for constructing covalent organic frameworks chiral membranes with a wide range of...

The development of chiral covalent organic framework (CCOF) membranes provides new opportunities for the large-scale separation of chiral drugs. Unfortunately, the contradiction between membrane flux and enantioselectivity, as well as the limitations on the variety of chiral selectors in CCOF membranes due to the complex membrane preparation processes, has hindered the development of this field. Herein, a rapid approach toward the assembly of CCOF membranes was developed by vacuum-assisted filtration. This fabrication method exhibits satisfactory universality, enabling the integration of a wide range of CCOFs containing different-sized chiral selectors (N-acetyl-L-cysteine and 6-deoxy-6-mercapto-β-cyclodextrin), even biomacromolecules (Pepsin). Under the optimal conditions, the racemic naproxen achieved effective enantiomer separation on three CCOF membranes by constant pressure filtration (e.e.% was 9.30 ~ 16.11% and J_s was 1.40 ~ 8.43 nmol cm^-2·h^-1, respectively). Molecular docking has demonstrated that three types of CCOF membranes achieve enantioselective adsorption of (S)-naproxen through multiple interactions. This work emphasizes that changes in preparation processes will help expand the CCOFs species applicable in chiral membrane technology.