title: Interactions of Lipidic Cubic Phase Nanoparticles with Lipid Membranes.
abstract: The interactions of liquid-crystalline monoolein (GMO) cubic phase nanoparticles with various model lipid membranes spread at the air-solution interface by the Langmuir technique were investigated. Cubosomes have attracted attention as potential biocompatible drug delivery systems, and thus understanding their mode of interaction with membranes is of special interest. Cubosomes spreading at the air-water interface as well as interactions with a monolayer of 1, 2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) compressed to different surface pressures were studied by monitoring surface pressure-time dependencies at constant area. Progressive incorporation of the nanoparticles was shown to lead to mixed monolayer formation. The concentration of cubosomes influenced the mechanism of incorporation, as well as the fluidity and permeability of the resulting lipid membranes. Brewster angle microscopy images reflected the dependence of the monolayer structure on the cubosomes presence in the subphase. A parameter Csat was introduced to indicate the point of saturation of the lipid membrane with the cubosomal material. This parameter was found to depend on the surface pressure showing that the cubosomes disintegrate in prolonged contact with the membrane, filling available voids in the lipid membrane. At highest surface pressures when the layer is most compact, the penetration of cubosomal material is not possible and only some exchange with the membrane lipid becomes the route of including GMO into the layer. Finally, comparative studies of the interactions between lipids with various headgroup charges with cubosomes suggest that at high surface pressure an exchange of lipid component between the monolayer and the cubosome in its intact form may occur.
authors.affiliation: Faculty of Chemistry, University of Warsaw , Pasteura 1, 02-093 Warsaw, Poland.
authors.forename: Elżbieta
authors.initials: E
authors.lastname: Jabłonowska
authors.affiliation: Faculty of Chemistry, University of Warsaw , Pasteura 1, 02-093 Warsaw, Poland.
authors.forename: Ewa
authors.initials: E
authors.lastname: Nazaruk
authors.affiliation: Faculty of Chemistry, Biological and Chemical Research Centre, University of Warsaw , Żwirki i Wigury 101, 02-089 Warsaw, Poland.
authors.forename: Dorota
authors.initials: D
authors.lastname: Matyszewska
authors.affiliation: Department of Health Sciences & Technology, ETH Zurich , 8092 Zurich, Switzerland.
authors.forename: Chiara
authors.initials: C
authors.lastname: Speziale
authors.affiliation: Department of Health Sciences & Technology, ETH Zurich , 8092 Zurich, Switzerland.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Mezzenga
authors.affiliation: Department of Chemistry, University of Zurich , Winterthurerstrasse 190, 8057 Zurich, Switzerland.
authors.forename: Ehud M
authors.initials: EM
authors.lastname: Landau
authors.affiliation: Faculty of Chemistry, University of Warsaw , Pasteura 1, 02-093 Warsaw, Poland.
authors.forename: Renata
authors.initials: R
authors.lastname: Bilewicz
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry*; D008055:Lipids / Q000737:chemistry*; D008563:Membrane Lipids / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D008055:Lipids; D008563:Membrane Lipids; D015060:1,2-Dipalmitoylphosphatidylcholine