Intrinsic chiral microporous polymer membranes by interfacial polymerization for precise enantioseparation

Enantiomers of chiral drugs frequently exhibit distinct pharmacological activities, metabolic pathways, rates of metabolism, and toxicological profiles. Consequently, the large-scale production of single enantiomers holds significant scientific and economic value. Membrane-based chiral separation presents considerable potential advantages, including low operational costs and high productivity, which have driven substantial research interest. In this study, we employed the chiral spirocyclic compound 1,1'-spirobiindane-7,7'-diol (SPINOL) as the aqueous-phase monomer to fabricate chiral polymers of intrinsic microporosity (CPIMs) membranes via interfacial polymerization (IP). The S-CPIMs/PAN composite membrane, synthesized on a polyacrylonitrile (PAN) substrate, demonstrated high enantioselectivity towards ibuprofen (PRF), achieving an enantiomeric excess ( ee ) of 95.4%. Mechanistically, this selectivity originates from transition-state energy differentials within transmembrane free-energy landscapes. Importantly, large-area, defect-free chiral membranes were successfully fabricated and engineered into functional membrane modules, which demonstrated exceptional homogeneity and stable performance.