Tanasescu, Radu Lanz, Martin A. Mueller, Dennis Tassler, Stephanie Ishikawa, Takashi Reiter, Renate Brezesinski, Gerald Zumbuehl, Andreas 2016-05-17 The artificial phospholipid Pad-PC-Pad was analyzed in 2D (monolayers at the air/water interface) and 3D (aqueous lipid dispersions) systems. In the gel phase, the two leaflets of a Pad-PC-Pad bilayer interdigitate completely, and the hydrophobic bilayer region has a thickness comparable to the length of a single phospholipid acyl chain. This leads to a stiff membrane with no spontaneous curvature. Forced into a vesicular structure, Pad-PC-Pad has faceted geometry, and in its extreme form, tetrahedral vesicles were found as predicted a decade ago. Above the main transition temperature, a noninterdigitated Lα phase with fluid chains has been observed. The addition of cholesterol leads to a slight decrease of the main transition temperature and a gradual decrease in the transition enthalpy until the transition vanishes at 40 mol % cholesterol in the mixture. Additionally, cholesterol pulls the chains apart, and a noninterdigitated gel phase is observed. In monolayers, cholesterol has an ordering effect on liquid-expanded phases and disorders condensed phases. The wavenumbers of the methylene stretching vibration indicate the formation of a liquid- ordered phase in mixtures with 40 mol % cholesterol. application/pdf https://folia.unifr.ch/global/documents/305134 https://folia.unifr.ch/documents/305134/files/zum_voi.pdf https://folia.unifr.ch/documents/305134/files/zum_voi_sm.pdf eng info:eu-repo/semantics/altIdentifier/doi/10.1021/acs.langmuir.6b01143 info:eu-repo/semantics/openAccess License undefined Langmuir. - 2016, vol. 32, no. 19, p. 4896–4903 info:eu-repo/classification/udc/54 Vesicle origami and the influence of cholesterol on lipid packing http://purl.org/coar/resource_type/c_6501