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Published on: August 3, 2021
How membrane permeation is affected by donor delivery solvent.
Bernard P Binks1, Paul D I Fletcher, Andrew J Johnson
1Surfactant & Colloid Group, Department of Chemistry, University of Hull, Hull, HU6 7RX, UK.
Physical Chemistry Chemical Physics : PCCP
|October 18, 2012
Summary
Switching donor solvents impacts membrane permeation by altering permeant partitioning. Our model quantitatively predicts these effects based on partition coefficients, validating experimental findings.
Area of Science:
- Physical Chemistry
- Materials Science
- Pharmacokinetics
Background:
- Membrane permeation is crucial for drug delivery and separation processes.
- Donor solvent choice significantly influences permeation dynamics.
- Understanding solvent effects requires a quantitative model linking partition coefficients to permeation rates.
Purpose of the Study:
- To investigate the theoretical and experimental effects of switching donor solvents (water vs. squalane) on membrane permeation.
- To develop and validate a model predicting permeation based on partition coefficients.
- To elucidate the mechanisms behind donor solvent effects in membrane transport.
Main Methods:
- Theoretical modeling based on rate-limiting membrane diffusion.
- Experimental measurement of permeation for various donor solvents, permeants, and membranes.
- Continuous monitoring of permeant concentration and determination of partition coefficients.
Main Results:
- A model was derived showing permeation depends on membrane-donor and membrane-receiver partition coefficients.
- Experimental results for hydrophilic/hydrophobic systems largely agreed with the model.
- Dominant solvent effects stem from altered permeant affinities, quantitatively predicted by partition coefficients.
Conclusions:
- The developed model successfully predicts membrane permeation changes due to donor solvent switching.
- Partition coefficients are key to understanding and quantifying solvent effects.
- Deviations from the model highlight additional solvent effects like altered rate-limiting steps or non-ideality.
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