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Updated: Jul 27, 2026
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Preparation of Light-responsive Membranes by a Combined Surface Grafting and Postmodification Process
Published on: March 21, 2014
Summary
Photochromic reactions enable membrane-based separation. Researchers concentrated carbon monoxide against a gradient using light-activated hemoglobin membranes, demonstrating reversible transport of ligands.
Area of Science:
- Membrane science
- Photochemistry
- Biophysical chemistry
Background:
- Carrier-mediated transport is crucial for separation processes.
- Photochromic reactions offer light-controllable mechanisms.
- Hemoglobin's interaction with ligands is well-documented.
Purpose of the Study:
- To investigate coupling photochromic reactions with carrier-mediated transport.
- To demonstrate light-induced concentration of permeants across a membrane.
- To explore the potential for selective separation using photoresponsive systems.
Main Methods:
- Utilizing a hemoglobin membrane for carrier-mediated transport.
- Employing differential illumination to trigger reversible photochromic reactions.
- Measuring concentration gradients of carbon monoxide.
Main Results:
- Carbon monoxide was successfully pumped against a fourfold concentration gradient.
- The extent of ligand concentration was directly related to light intensity.
- The observed concentration effect was reversible.
Conclusions:
- Reversible photochromic reactions can drive carrier-mediated transport for separation.
- Light intensity modulates the concentration of photochromic ligands.
- This approach allows for the transport of non-photochemically sensitive ligands via photosensitive carriers.
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