Hierarchically Self-Assembled Anion-Coordination-Driven Gels for Guest Segregation and Electrical Sensing

The search for macroscopic materials with differentially addressable spaces based on molecular containers has long been driven by their great potential for diverse practical applications pertaining guest selective capture and release. Herein, we report a class of gels (G^1-NH2, G^1-UPy, G^2-NH2, and G^2-UPy) that are formed through hierarchical self-assembly of anion-coordinated architectures. The well-defined shapes and sizes of the cavities within anion-coordinated architectures endow the gels with different internal phases, which is beneficial to differentiate the release profiles of guest molecules (dimethylethanolamine, choline, and propyl trimethylammonium) depending on their binding affinity. This study also introduces the concept of flowing a solution containing guests through a host-containing gel for effective guest separation. The process of guest binding could be also monitored in real time via electrical characterization. This work may thus provide a useful strategy for selective solid-phase molecular separation.