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Updated: Oct 23, 2025
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Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
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Synthetic Macrocycle Nanopore for Potassium-Selective Transmembrane Transport
Dan Qiao1, Himanshu Joshi2, Huangtianzhi Zhu3
1Laboratory of Experimental Physical Biology, Department of Chemistry, Zhejiang University, Hangzhou 310027, China.
Journal of the American Chemical Society
|August 17, 2021
Summary
Chemically synthesized extended pillararene macrocycles create precisely shaped synthetic nanopores. These novel synthetic nanopores demonstrate selective ion transport across lipid membranes, advancing membrane filtration and sensing technologies.
Area of Science:
- Supramolecular Chemistry
- Membrane Biophysics
- Nanotechnology
Background:
- Synthetic nanopores mimic biological channels for filtration and sensing.
- Current synthetic nanopores lack precise atomic-level control over shape and chemical group placement.
- Achieving atomically defined synthetic nanopores is a significant challenge.
Purpose of the Study:
- To introduce a chemically defined transmembrane nanopore using a novel macromolecule.
- To demonstrate selective ion transport through the synthetic nanopore.
- To explore the potential of direct chemical synthesis for designing custom nanopore functionalities.
Main Methods:
- Synthesis of an extended pillararene macrocycle (EPM).
- Incorporation of individual EPM nanopores into lipid bilayer membranes.
- Ionic current measurements to assess nanopore stability and ion transport selectivity.
Main Results:
- Stable insertion of individual EPM nanopores into lipid bilayers was confirmed.
- Remarkable cation type-selective transport was observed.
- Up to a 21-fold selectivity for potassium ions over sodium ions was achieved.
Conclusions:
- Direct chemical synthesis enables the de novo design of synthetic nanopores.
- Extended pillararene macrocycles serve as chemically defined transmembrane nanopores.
- These synthetic nanopores offer custom transport functionality based on their atomically defined structure.
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