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Photolipid Bilayer Permeability is Controlled by Transient Pore Formation
Stefanie D Pritzl1, Patrick Urban1, Alexander Prasselsperger1
1Chair for Photonics and Optoelectronics, Nano-Institute Munich, Department of Physics, Ludwig-Maximilians-Universität (LMU), Königinstraße 10, 80539 Munich, Germany.
Langmuir : the ACS Journal of Surfaces and Colloids
|November 4, 2020
Summary
Synthetic photolipids enable controlled drug delivery by reversibly switching membrane permeability. This light-induced pore formation in lipid bilayers enhances molecule release for bioengineering and therapeutic applications.
Area of Science:
- Biomaterials Science
- Membrane Biophysics
- Drug Delivery Systems
Background:
- Controlling molecular release from liposomes is crucial for drug delivery and bioengineering.
- Synthetic lipids offer tunable properties for advanced applications.
Purpose of the Study:
- To investigate the light-induced changes in membrane permeability of azobenzene-containing phosphatidylcholine (azo-PC) photolipids.
- To understand the mechanism of transient pore formation and its relation to photolipid isomerization.
Main Methods:
- Preparation and characterization of giant unilamellar vesicles (GUVs) from azo-PC photolipids.
- Irradiation experiments using UV-A and visible light to induce photoswitching.
- Fluorescent dye leakage assays to quantify membrane permeability.
- Langmuir-Blodgett and patch-clamp measurements to analyze pore formation.
Main Results:
- Irradiation of azo-PC GUVs with UV-A and visible light induced significant leakage of encapsulated fluorescent dyes.
- Permeability increase was attributed to the formation of transient pores in the lipid bilayer.
- Pore formation mechanism involves area fluctuations and changes in the cross-sectional area during trans-to-cis and cis-to-trans isomerization of azo-PC molecules.
Conclusions:
- Reversible photoswitching of azo-PC photolipids provides a mechanism for light-controlled modulation of membrane permeability.
- This light-gated permeability control is a promising strategy for targeted drug delivery and synthetic biology applications.
- The study elucidates the photophysical basis of light-induced pore formation in synthetic lipid bilayers.
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