1.D.184.  Ion-selective Crown-ether Crystal Pore (IS-CE-P) Family

Artificial solid-state ionic devices enable separation technologies. Ye et al. 2021 reported an artificial sodium-selective ionic device, built on synthesized porous crown-ether crystals which consist of densely packed 0.26-nm-wide pores. The Na⁺ selectivity of the artificial sodium-selective ionic device reached 15 against K ⁺, which is comparable to the biological counterpart, 523 against Ca^{2 +} , which is nearly two orders of magnitude higher than the biological one, and 1128 against Mg^{2 +} . The selectivity may arise from the size effect and molecular recognition effect.

Crown ethers (CEs) are widely studied in the area of artificial ion channels owing to their intrinsic host-guest interaction with different kinds of organic and inorganic ions. Other advantages such as lower price, chemical stability, and easier modification also make CE a research hotspot in the field of synthetic transmembrane nanopores. And numerous CEs-based membrane-active synthetic ion channels were designed and fabricated in the past. Recent progress of CEs-based synthetic ion transporters has been comprehensively summarized in a review, including their design principles, functional mechanisms, controllable properties, and biomedical applications (He et al. 2023).