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Updated: Jul 14, 2026
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Single-Molecule Diffusion and Assembly on Polymer-Crowded Lipid Membranes
Published on: July 19, 2022
Passive diffusion of polymeric surfactants across lipid bilayers
Frédéric Mathot1, A Schanck, F Van Bambeke
1Université Catholique de Louvain, Unité de Pharmacie Galénique, UCL, Brussels, Belgium.
Summary
Monomethylether poly(ethylene glycol)-poly(caprolactone-co-trimethylene carbonate) [mmePEG(750)P(CL-co-TMC)] polymeric surfactants passively diffuse across lipid membranes. These surfactants can cross enterocyte models without compromising membrane integrity, suggesting potential for drug delivery applications.
Area of Science:
- Polymer chemistry
- Biomaterials science
- Drug delivery systems
Background:
- Self-assembling polymeric surfactants enhance drug solubility and membrane permeability.
- Understanding the interaction of polymeric surfactants with biological membranes is crucial for drug delivery.
Purpose of the Study:
- To investigate the passive diffusion of mmePEG(750)P(CL-co-TMC) across lipid bilayers using the Parallel Artificial Membrane Permeability Assay (PAMPA).
- To evaluate the effect of mmePEG(750)P(CL-co-TMC) on the properties of liposomal lipid bilayers.
Main Methods:
- Parallel Artificial Membrane Permeability Assay (PAMPA) using an enterocyte-mimicking membrane.
- Liposome-based assays to assess membrane properties like rigidity and permeability.
Main Results:
- The mmePEG(750)P(CL-co-TMC) polymer demonstrated passive diffusion across the PAMPA membrane at non-disruptive concentrations.
- A slight rigidification and minor increase in permeability were observed in liposomal lipid bilayers upon interaction with the polymer.
Conclusions:
- Polymeric surfactants like mmePEG(750)P(CL-co-TMC) can permeate lipid membranes via passive diffusion.
- These surfactants interact with lipid bilayers, causing subtle changes in membrane properties, which warrants further investigation for drug delivery efficacy.
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