1.D.306.  The Helical Folded Na+ NanoPore (HFS-NP) Family 

Zhang et al. 2024 designed and synthesized a series of helically folded nanopores by employing a quinoline-oxadiazole structural sequence to finely replicate the pentahydrate structure of sodium ions Tthese nanopores are capable of achieving sodium transmembrane permeation with ion selectivity at the level of natural sodium channels, as observed in rationally designed nanopores with a Na⁺/K⁺ ion selectivity ratio of up to 20.4. Slight structural variations in nanopore structures can switch ion transport modes between the channel and carrier. Compared to the carrier mode, the channel mode not only transports ions faster but also has higher ion selectivity during transmembrane conduction, clearly illustrating that the trade-off phenomenon between ion selectivity and transport activity does not occur between the two transport modes of channel and carrier. Zhang et al. 2024 also found that the spatial position and numbers of coordination sites are crucial for the sodium ion selectivity. Carrier M1 reported in this work is totally superior to the commercial Na⁺ carrier ETH2120, especially in terms of Na⁺/K⁺ ion selectivity, thus being a potentially practical Na⁺ carrier. This study provides a new paradigm on the rational design of sodium-specific synthetic nanopores, which will open up the possibility for the application of artificial sodium-specific transmembrane permeation in biomedicine and disease treatment (Zhang et al. 2024).