Light-Gating Crystalline Porous Covalent Organic Frameworks
Guangtong Wang1, Yu Feng2, Xingyao Ye3
1School of Medicine and Health, Harbin Institute of Technology, Harbin 150080, China.
Journal of the American Chemical Society
|April 2, 2024
Summary
We developed photoadaptable covalent organic frameworks with light-controlled 1D nanochannels. These materials can gate molecular adsorption and release, offering a platform for light-responsive delivery systems.
Area of Science:
- Materials Science
- Nanotechnology
- Supramolecular Chemistry
Background:
- Covalent organic frameworks (COFs) offer tunable porosity and stability.
- Controlling molecular transport within nanochannels remains a challenge.
Purpose of the Study:
- To engineer photoadaptable 1D nanochannels within COFs for light-gated molecular transport.
- To investigate the impact of light-induced structural changes on molecular adsorption and release.
Main Methods:
- Synthesis of crystalline porous COFs with integrated tetrafluoro-substituted azobenzene units.
- Characterization of photoisomerization effects on pore shape, size, and polarity.
- Testing molecular adsorption and controlled release of various compounds (iodine, dyes, drugs, enzymes).
Main Results:
- Achieved light-gating in 1D nanochannels via photoisomerization of azobenzene units.
- Demonstrated significant changes in intrapore polarity and pore dimensions upon light exposure.
- Observed rapid, light-controlled adsorption and release of diverse molecules, including drugs and enzymes.
Conclusions:
- Photoadaptable COFs provide a versatile platform for light-responsive porous materials.
- The developed system enables remote, light-controlled molecular delivery and separation.
- This technology opens avenues for advanced drug delivery and sensing applications.
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