Cholesterol-phospholipid interactions: new insights from surface x-ray scattering data.
We report a structural study of cholesterol-DPPC (1,2-dipalmitoyl-sn-glycero-3-phophocholine) monolayers using x-ray reflectivity and grazing incidence x-ray diffraction. Reflectivity reveals that the vertical position of cholesterol relative to phospholipids strongly depends on its mole fraction (chi(CHOL)). Moreover, we find that at a broad range of chi(CHOL) cholesterol and DPPC form alloylike mixed domains of short-range order and the same stoichiometry as that of the film. Based on the data presented, we propose a new model of cholesterol-phospholipid organization in mixed monolayers.
Ivankin
Andrey
A
Center for Molecular Study of Condensed Soft Matter (muCoSM), and Division of Physics, BCPS Department, Illinois Institute of Technology, Chicago, Illinois 60616, USA.
Kuzmenko
Ivan
I
Gidalevitz
David
D
D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D002784:Cholesterol / Q000737:chemistry*; D008956:Models, Chemical; D014961:X-Ray Diffraction
D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol