Abstract
Epifluorescence microscopy is used to determine phase diagrams for lipid monolayers containing binary mixtures of cholesterol or dihydrocholesterol and dimyristoylphosphatidylserine, as well as ternary mixtures that also contain ganglioside GM1. The phase diagrams are unusual in that they show multiple critical points: two upper miscibility critical points and one lower miscibility critical point. These critical points all are associated with the formation of condensed complexes between these lipids and cholesterol (or dihydrocholesterol). The miscibility critical pressures depend on subphase pH and ionic strength. Changes in critical pressures due to changes in subphase composition are closely related to changes in membrane electrostatic pressure and surface ionization.
Original language | English (US) |
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Pages (from-to) | 13391-13396 |
Number of pages | 6 |
Journal | Proceedings of the National Academy of Sciences of the United States of America |
Volume | 99 |
Issue number | 21 |
DOIs | |
State | Published - Oct 15 2002 |
Keywords
- Condensed complexes
- Liquid immiscibility
- Phase diagrams
- Phospholipids
- Sphingomyelin
ASJC Scopus subject areas
- General