Fluorofoldamer-Based Salt- and Proton-Rejecting Artificial Water Channels for Ultrafast Water Transport.

Jie Shen, Arundhati Roy, Himanshu Joshi, Laxmicharan Samineni, Ruijuan Ye, Yu-Ming Tu, Woochul Song, Matthew Skiles, Manish Kumar, Aleksei Aksimentiev, and Huaqiang Zeng
Nano Lett 22(12) 4831-4838 (2022)
DOI:10.1021/acs.nanolett.2c01137  PMID:35674810  BibTex

Here, we report on a novel class of fluorofoldamer-based artificial water channels (AWCs) that combines excellent water transport rate and selectivity with structural simplicity and robustness. Produced by a facile one-pot copolymerization reaction under mild conditions, the best-performing channel (AWC ) is an n-CH-decorated foldamer nanotube with an average channel length of 2.8 nm and a pore diameter of 5.2 Å. AWC demonstrates an ultrafast water conduction rate of 1.4 × 10 HO/s per channel, outperforming the archetypal biological water channel, aquaporin 1, while excluding salts (i.e., NaCl and KCl) and protons. Unique to this class of channels, the inwardly facing C(sp2)-F atoms being the most electronegative in the periodic table are proposed as being critical to enabling the ultrafast and superselective water transport properties by decreasing the channel's cavity and enhancing the channel wall smoothness via reducing intermolecular forces with water molecules or hydrated ions.