pH-responsive nanopores enable programmable transmembrane potential
Year: 2026
Type: preprint
Abstract: Biological ion channels achieve highly selective, ultrafast ion transport through stimulus-responsive gating, in which conformational changes triggered by chemical cues such as pH that modulate channel permeability with exquisite precision. Replicating this coupled chemical-structural functionality in synthetic membranes remains a fundamental challenge, particularly for scalable platforms relevant to energy harvesting, desalination, and chemical sensing. Here, we report a bioinspired polymer-metal-organic framework (MOF) composite membrane in which an amino acid (histidine) functionalized MOF nanopores serve as synthetic proton-gated anion channel. The histidine modified, spatially confined ion transport pathway exhibited selective Cl- diffusion at pH 4, enabling pH programmable control of transmembrane potential. Micrometer-scale percolated transport networks within the composite membrane, architecturally inspired by ion channels embedded in lipid bilayers, translate localized αNH2(histidine)-anion specific interaction into macroscopic, anion selective transmembrane potential output. This work establishes a generalizable design strategy for coupling chemical gating with macroscopic ion transport in synthetic membrane systems, with direct implications for ion separations, sensing and osmotic energy generation.
Source: ChemRxiv
Language: English
Subfield: Biomedical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7220399188