title: Size fractionation and size characterization of nanoemulsions of lipid droplets and large unilamellar lipid vesicles by asymmetric-flow field-flow fractionation/multi-angle light scattering and dynamic light scattering.
abstract: Asymmetric-flow field-flow fractionation technique coupled to a multi-angle light-scattering detector (AF4-MALS) was used together with dynamic light-scattering (DLS) in batch mode and transmission electron microscopy (TEM) to study the size characteristics of the trioleoylglycerol lipid droplets covered by a monolayer of sphingomyelin and cholesterol, in water phase. These lipid droplet nanoemulsions (LD) were formed by ultrasonication. In parallel, the size characteristics of large unilamellar lipid vesicles (LUV) prepared by extrusion and composed of sphingomyelin and cholesterol were determined. LD and LUV were prepared at two different molar ratios (1/1, 4/1) of sphingomyelin and cholesterol. In AF4-MALS, various cross-flow conditions and mobile phase compositions were tested to optimize the separation of LD or LUV particles. The particle radii, R, as well as the root-mean-square radii, Rrms, of LD and LUV were determined by AF4-MALS, whereas the hydrodynamic radii, Rh, were obtained by DLS. TEM visualization revealed round shape particles of LD and LUV.
authors.affiliation: University of Ljubljana, Biotechnical faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Valerija
authors.initials: V
authors.lastname: Vezočnik
authors.affiliation: National Institute of Chemistry, Laboratory for Polymer Chemistry and Technology, Hajdrihova 19, 1000 Ljubljana, Slovenia.
authors.forename: Katja
authors.initials: K
authors.lastname: Rebolj
authors.affiliation: National Institute of Chemistry, Laboratory for Polymer Chemistry and Technology, Hajdrihova 19, 1000 Ljubljana, Slovenia.
authors.forename: Simona
authors.initials: S
authors.lastname: Sitar
authors.affiliation: University of Ljubljana, Biotechnical faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Katja
authors.initials: K
authors.lastname: Ota
authors.affiliation: National Institute of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Magda
authors.initials: M
authors.lastname: Tušek-Žnidarič
authors.affiliation: University of Ljubljana, Biotechnical faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Jasna
authors.initials: J
authors.lastname: Štrus
authors.affiliation: University of Ljubljana, Biotechnical faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia.
authors.forename: Kristina
authors.initials: K
authors.lastname: Sepčić
authors.affiliation: National Institute of Chemistry, Laboratory for Polymer Chemistry and Technology, Hajdrihova 19, 1000 Ljubljana, Slovenia.
authors.forename: David
authors.initials: D
authors.lastname: Pahovnik
authors.affiliation: University of Ljubljana, Biotechnical faculty, Department of Biology, Večna pot 111, 1000 Ljubljana, Slovenia. Electronic address: peter.macek@bf.uni-lj.si.
authors.forename: Peter
authors.initials: P
authors.lastname: Maček
authors.affiliation: National Institute of Chemistry, Laboratory for Polymer Chemistry and Technology, Hajdrihova 19, 1000 Ljubljana, Slovenia. Electronic address: ema.zagar@ki.si.
authors.forename: Ema
authors.initials: E
authors.lastname: Žagar
mesh_terms: D002784:Cholesterol / Q000737:chemistry*; D000067493:Dynamic Light Scattering; D031521:Fractionation, Field Flow / Q000379:methods; D008027:Light; D066292:Lipid Droplets / Q000737:chemistry*; D046529:Microscopy, Electron, Transmission; D010316:Particle Size; D012542:Scattering, Radiation; D013109:Sphingomyelins / Q000737:chemistry*; D014304:Triolein / Q000737:chemistry*; D053835:Unilamellar Liposomes / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D013109:Sphingomyelins; D053835:Unilamellar Liposomes; D014867:Water; D014304:Triolein; D002784:Cholesterol
keywords: Cholesterol; Field-flow fractionation; Lipid droplets; Lipid vesicles; Particle size; Sphingomyelin