A Funnel-Shaped Chloride Nanochannel Inspired By ClC Protein

Abstract

Chloride transport participates in a great variety of physiological activities, such as regulating electrical excitability and maintaining acid–base equilibrium. However, the high flux is the prerequisite to ensure the realization of the above functions. Actually, the high flux of ion transport is significant, not only for living things but also for practical applications. Herein, inspired by chloride channel (ClC) protein, a novel NH2-pillar­[5]­arene functionalized funnel-shaped nanochannel was designed and constructed. The introduction of functional molecules changed surface charge property and endowed the nanochannel with Cl– selectivity, which facilitated Cl– transport. Moreover, by adjusting the asymmetric degree of the nanochannel, the Cl– transport flux can be improved greatly. The successful construction of an artificial ion channel with high flux will be much useful for practical applications like microfluidic devices, sensors, and ion separation.

Angstrom-scale ion channels towards single-ion selectivity

“…In another case by Cheng et al, a novel NH 2 -pillar [5]arene (NH 2 -P5A) decorated funnel-shaped channel was constructed inspired by ClC protein channel. 239 NH 2 -P5A molecules were grafted to the PET nanochannel through an amide condensation reaction. The introduced NH 2 -P5A modulates the surface charge and selectively binds Cl À via hydrogen-bonding interaction, facilitating Cl À transport through the channel.…”

Biomimetic Nanochannels: From Fabrication Principles to Theoretical Insights

“…designed novel NH 2 ‐pillar[5]arene functionalized funnel‐shaped nanochannel (NH 2 ‐P5A channel) for Cl − transport. [ 73 ] By regulating shapes of channels, significant enhancement can be found in Cl − concentration and potential difference along channels, leading to increasement of transport flux of Cl − . Besides, Hou et al.…”

“…More recently, Li et al designed novel NH 2 -pillar [5]arene functionalized funnelshaped nanochannel (NH 2 -P5A channel) for Cl − transport. [73] By regulating shapes of channels, significant enhancement can be found in Cl − concentration and potential difference along channels, leading to increasement of transport flux of Cl − . Besides, Hou et al reported recognition of multivalent metal ions through tannic acid modified single glass nanopore depending on the different binding energies between poly phenolic groups and metal ions.…”

Unimolecular Helix-Based Transmembrane Nanochannel with a Smallest Luminal Cavity of 1 Å Expressing High Proton Selectivity and Transport Activity

“…In living systems, proton transport is essential for regulating the pH level of some tissues or organelles to facilitate specific physiological functions, which is usually mediated by specific protein channels. , For instance, the ATP-driven proton channel (i.e., proton ATPase) on lysosome or gastric parietal cells can efficiently acidify their interior environment for accelerating the digestive process. , As is known, dysfunctions of protein channels may lead to severe ion channelopathies such as arrhythmia, cystic fibrosis, gastric ulcers, etc. Developing artificial ion channels not only helps in understanding the structure–function relationship of natural protein channels but also contributes to the develop of potential treatment for ion-transport related diseases. − To date, a myriad of artificial channels for transport of cations, , anions, , water, − or small organic molecules , have been fabricated. Nevertheless, synthetic proton channels with selective and rapid transport capabilities are rarely explored.…”