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Phase Diagram Characterization Using Magnetic Beads as Liquid Carriers
Published on: September 4, 2015
Path dependence of three-phase or two-phase end points in fluid binary lipid mixtures
Emily R Lamberson1, Lee R Cambrea, Jean-Christophe Rochet
1Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA.
The Journal of Physical Chemistry. B
|February 27, 2009
Summary
Controlling the charge state of anionic lipids in mixtures with zwitterionic lipids influences phase behavior. The order of manipulating charge state determines whether a two- or three-phase system emerges, showing biological system flexibility.
Area of Science:
- Biophysics
- Materials Science
Background:
- Anionic and zwitterionic lipid mixtures exhibit tunable phase behavior.
- The charge state of anionic lipids is a key factor in controlling mixture phase separation.
Purpose of the Study:
- To investigate how manipulating the charge state of anionic lipids affects the phase behavior of anionic/zwitterionic mixtures.
- To demonstrate the influence of manipulation order on the final phase state.
Main Methods:
- Studied mixtures of dioleoylphosphatidic acid (DOPA) and dioleoylphosphatidylcholine (DOPC).
- Manipulated the charge state of DOPA through protonation and calcium complexation.
- Observed phase behavior transitions in response to charge state changes.
Main Results:
- Demixing of DOPA/DOPC mixtures occurs upon DOPA protonation or formation of DOPA(2-):Ca(2+) complexes.
- The final phase behavior (two-phase or three-phase system) depends on the sequence of charge state manipulation.
- Different phase endpoints are readily accessible by controlling the order of charge manipulation.
Conclusions:
- The phase behavior of anionic/zwitterionic lipid mixtures is highly sensitive to the anionic lipid's charge state.
- The order of manipulating charge state offers a flexible method to control the final phase behavior of lipid mixtures.
- This flexibility highlights the adaptability of biological membrane systems.
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