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PIP-on-a-chip: A Label-free Study of Protein-phosphoinositide Interactions
Published on: July 27, 2017
Electrostatic effects on deposition of multiple phospholipid bilayers at oxide surfaces
Timothy A Oleson1, Nita Sahai, Joel A Pedersen
1Department of Geoscience, 1215 West Dayton Street, University of Wisconsin, Madison, WI 53706, USA. toleson@geology.wisc.edu
Journal of Colloid and Interface Science
|September 28, 2010
Summary
Electrostatic forces and ionic strength influence supported phospholipid bilayer (SPB) formation on oxide particles. These findings impact biomaterials and origin-of-life studies.
Area of Science:
- Surface science
- Biophysics
- Materials science
Background:
- Understanding supported phospholipid bilayers (SPB) is crucial for various applications.
- Current knowledge relies heavily on planar substrates, limiting insights into particle-based systems.
Purpose of the Study:
- To investigate electrostatic effects on SPB formation using oxide particles.
- To explore the influence of substrate type, ionic strength, divalent cations, and phospholipid charge.
Main Methods:
- Experiments using aqueous suspensions of quartz and corundum particles.
- Utilizing fluorescent dye-loaded dipalmitoylphosphatidylcholine (DPPC) vesicles.
- Analyzing adsorption isotherms for DPPC, dipalmitoylphosphatidylserine (DPPS), and dipalmitoylethylphosphatidylcholine (DPEPC).
Main Results:
- Vesicles ruptured upon contact with oxide particles, forming supported planar bilayers.
- Van der Waals forces primarily drive the formation of two DPPC bilayers.
- Low ionic strength promotes additional DPPC bilayer adsorption via electric double-layer extension.
- Repulsive forces between charged bilayers and oxide surfaces limit adsorption of charged phospholipids (DPPS, DPEPC).
Conclusions:
- Electrostatic interactions and ionic strength are key determinants of SPB formation on particle surfaces.
- Findings offer insights into SPB applications in biomedicine, industry, and environmental remediation.
- Results contribute to understanding proto-cell stability in origin-of-life hypotheses.
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