title: Cholesterol: lecithin association at molecular ratios of up to 2 : 1.
abstract: X-ray diffraction studies of cholestol: egg lecithin mixtures have demonstrated that single phase systems with molecular ratios of up to 2 : 1 can be prepared from solutions in chloroform but that mixtures prepared from ethanol solutions form a single phase only up to a maximum molecular ratio of 1 : 1. The low angle X-ray patterns of the two mixtures (2 : 1 and 1 : 1) are quite distinctive but there is only a small difference in the wide angle spacings. Independent cholesterol reflections begin to appear in the X-ray diffraction pattern of the 2 : 1 mixture after a few days even when the dry sample is contained in a sealed glass capillary tube. Addition of water greatly accelerates this process. In contrast, a 2 : 1 mixture prepared from chloroform solutions can be maintained in sonicated dispersions in water for long periods.
mesh_terms: D001665:Binding Sites; D002725:Chloroform; D002784:Cholesterol; D004530:Egg Yolk; D005260:Female; D007700:Kinetics; D008968:Molecular Conformation; D010713:Phosphatidylcholines; D013997:Time Factors; D014867:Water; D014961:X-Ray Diffraction
chemical_list: D010713:Phosphatidylcholines; D014867:Water; D002725:Chloroform; D002784:Cholesterol