title: Nano electrospray gas-phase electrophoretic mobility molecular analysis (nES GEMMA) of liposomes: applicability of the technique for nano vesicle batch control.
abstract: Liposomes are biodegradable nanoparticle vesicles consisting of a lipid bilayer encapsulating an aqueous core. Entrapped cargo material is shielded from the extra-vesicular medium and sustained release of encapsulated material can be achieved. However, application of liposomes as nano-carriers demands their characterization concerning size and size distribution, particle-number concentration, occurrence of vesicle building blocks in solution and determination of the resulting vesicle encapsulation capacity. These questions can be targeted via gas-phase electrophoretic mobility molecular analysis (GEMMA) based on a nano electrospray (nES) charge-reduction source. This instrument separates single-charged nanoparticles in the gas-phase according to size in a high-laminar sheath-flow by means of an orthogonal, tunable electric field. nES GEMMA analysis enables to confirm liposome integrity after passage through the instrument (in combination with atomic force microscopy) as well as to exclude vesicle aggregation. Additionally, nanoparticle diameters at peak apexes and size distribution data are obtained. Differences of hydrodynamic and dry particle diameter values, as well as the effect of number- and mass-based concentration data analysis on obtained liposome diameters are shown. Furthermore, the repeatability of liposome preparation is studied, especially upon incorporation of PEGylated lipids in the bilayer. Finally, the instruments applicability to monitor mechanical stress applied to vesicles is demonstrated.
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria. guenter.allmaier@tuwien.ac.at.
authors.forename: Victor U
authors.initials: VU
authors.lastname: Weiss
authors.affiliation: Department of Surgery, University of Lund, Lund, Sweden.
authors.forename: Carlos
authors.initials: C
authors.lastname: Urey
authors.affiliation: Department of Environmental Geosciences and Environmental Science Research Network, University of Vienna, Vienna, Austria.
authors.forename: Andreas
authors.initials: A
authors.lastname: Gondikas
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria. guenter.allmaier@tuwien.ac.at.
authors.forename: Monika
authors.initials: M
authors.lastname: Golesne
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria. guenter.allmaier@tuwien.ac.at.
authors.forename: Gernot
authors.initials: G
authors.lastname: Friedbacher
authors.affiliation: Department of Environmental Geosciences and Environmental Science Research Network, University of Vienna, Vienna, Austria.
authors.forename: Frank
authors.initials: F
authors.lastname: von der Kammer
authors.affiliation: Department of Environmental Geosciences and Environmental Science Research Network, University of Vienna, Vienna, Austria.
authors.forename: Thilo
authors.initials: T
authors.lastname: Hofmann
authors.affiliation: Department of Surgery, University of Lund, Lund, Sweden.
authors.forename: Roland
authors.initials: R
authors.lastname: Andersson
authors.affiliation: Biomedical Center, University of Lund, Lund, Sweden.
authors.forename: György
authors.initials: G
authors.lastname: Marko-Varga
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria. guenter.allmaier@tuwien.ac.at.
authors.forename: Martina
authors.initials: M
authors.lastname: Marchetti-Deschmann
authors.affiliation: Institute of Chemical Technologies and Analytics, TU Wien, Vienna, Austria. guenter.allmaier@tuwien.ac.at.
authors.forename: Günter
authors.initials: G
authors.lastname: Allmaier
mesh_terms: D004586:Electrophoresis; D005740:Gases; D008055:Lipids / Q000737:chemistry; D008081:Liposomes / Q000032:analysis*; D018625:Microscopy, Atomic Force; D010316:Particle Size
chemical_list: D005740:Gases; D008055:Lipids; D008081:Liposomes