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Automated Lipid Bilayer Membrane Formation Using a Polydimethylsiloxane Thin Film
Published on: July 10, 2016
Charge properties of membranes modified by multilayer polyelectrolyte adsorption
Abdoul-Nasser Dirieh Egueh1, Boris Lakard, Patrick Fievet
1Université de Franche-Comté, Institut UTINAM-UMR CNRS 6213, 16 Route de Gray, 25030 Besançon Cedex, France.
Journal of Colloid and Interface Science
|January 26, 2010
Summary
Polyelectrolyte multilayers were built on polyethersulfone membranes. Zeta potential varied with concentration, and solute flux decreased, indicating functionalized membranes offer greater diffusion resistance.
Area of Science:
- Materials Science
- Surface Chemistry
- Membrane Technology
Background:
- Polyethersulfone (PES) membranes are widely used in separation processes.
- Functionalizing membrane surfaces can alter their properties and performance.
- Understanding surface charge and diffusion is crucial for membrane design.
Purpose of the Study:
- To investigate the surface properties of PES membranes modified with polyelectrolyte multilayers (PEMs).
- To characterize the influence of PEMs on membrane surface charge and solute diffusion.
- To explore the effect of polyelectrolyte concentration on PEM formation and properties.
Main Methods:
- Tangential streaming potential measurements to assess outer surface zeta potential.
- Diffusion experiments to quantify solute flux through modified membranes.
- Membrane potential measurements to probe inner pore wall characteristics.
Main Results:
- Zeta potential of PEMs exhibited periodic positive/negative variations at high polyelectrolyte concentrations (10 g/L).
- PEMs formed from lower concentrations (1 and 5 g/L) resulted in consistently positive zeta potentials.
- Solute flux significantly decreased after membrane functionalization with PEMs.
- Evidence suggests modification of pore wall charges, though contribution is hard to distinguish.
Conclusions:
- Alternate adsorption of polyanions and polycations effectively modifies PES membrane surfaces.
- PEM formation and resulting surface charge are dependent on polyelectrolyte concentration.
- Functionalized membranes demonstrate increased diffusional resistance, impacting separation performance.
- PEMs alter membrane surface properties, offering potential for tailored filtration applications.
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