Polyhydrazide‐Based Organic Nanotubes as Efficient and Selective Artificial Iodide Channels. Issue 12 (4th February 2020)

• Record Type: Journal Article
• Authors: Roy, Arundhati; Joshi, Himanshu; Ye, Ruijuan; Shen, Jie; Chen, Feng; Aksimentiev, Aleksei; Zeng, Huaqiang
• Is Part Of: Angewandte Chemie international edition. Volume 59:Issue 12(2020)
• Page Start: 4806
• Page End: 4813
• Publication Date: 2020-02-04
• Subjects: hydrogen bonds -- ion channels -- iodide -- molecular dynamics -- supramolecular chemistry; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201916287
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: Reported herein is a series of pore‐containing polymeric nanotubes based on a hydrogen‐bonded hydrazide backbone. Nanotubes of suitable lengths, possessing a hollow cavity of about a 6.5 Å diameter, mediate highly efficient transport of diverse types of anions, rather than cations, across lipid membranes. The reported polymer channel, having an average molecular weight of 18.2 kDa and 3.6 nm in helical height, exhibits the highest anion‐transport activities for iodide ( EC 50 =0.042 μm or 0.028 mol % relative to lipid), whcih is transported 10 times more efficiently than chlorides ( EC 50 =0.47 μm ). Notably, even in cholesterol‐rich environment, iodide transport activity remains high with an EC 50 of 0.37 μm . Molecular dynamics simulation studies confirm that the channel is highly selective for anions and that such anion selectivity arises from a positive electrostatic potential of the central lumen rendered by the interior‐pointing methyl groups. Abstract : The right channels : A novel class of foldamer‐based pore‐forming helically folded polyhydrazides, having hydrophobic cavities of about a 6.5 Å diameter, promote transport of anions, rather than cations, across membranes, with iodide as the preferred transport species. The best channel, having a helical height of 3.6 nm, exhibits the highest recorded iodide transport activity ( EC 50 =0.042 μm or 0.028 mol % relative to lipid) and high I − /Cl − selectivity of 11, in terms of EC 50 values, or 42 based on initial rate constants.