Chiral-functionalized membranes for chiral drugs sieving

Current trend that integrates chiral designs into robust membrane systems is providing distinct horizons for the development of chiral separation technology. However, creating chiral sites in-between membrane laminates is still an open issue. Herein, we demonstrate a decorated layered chitosan/graphene oxide (CG) membrane via non-covalent interactions with L-tryptophan derivatives (LPWM), yielding materials with chiral functionality and superior mechanical strength. LPWM introduces chiral environment into the membrane, giving rise to visual recognition sensitivity and decent enantioseparation performance toward chiral drug molecules, with optical isomeric excess value exceeding 80% for pseudoephedrine (PEP). The chiral discrimination is associated with preferential binding of one of the isomers due to stronger or additional H-bonds with chiral assemblies. This work not only paves a new way for the fabrication of chiral membranes via a simple non-covalent interaction, but also guides a potential direction to realize enantioseparation employing decorated laminated membranes.