title: Cholesterol-phospholipid interactions: new insights from surface x-ray scattering data.
abstract: 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.
authors.affiliation: Center for Molecular Study of Condensed Soft Matter (muCoSM), and Division of Physics, BCPS Department, Illinois Institute of Technology, Chicago, Illinois 60616, USA.
authors.forename: Andrey
authors.initials: A
authors.lastname: Ivankin
authors.forename: Ivan
authors.initials: I
authors.lastname: Kuzmenko
authors.forename: David
authors.initials: D
authors.lastname: Gidalevitz
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry*; D002784:Cholesterol / Q000737:chemistry*; D008956:Models, Chemical; D014961:X-Ray Diffraction
chemical_list: D015060:1,2-Dipalmitoylphosphatidylcholine; D002784:Cholesterol