title: Lipid phase behavior studied with a quartz crystal microbalance: A technique for biophysical studies with applications in screening.
abstract: Quartz crystal microbalance (QCM) is emerging as a versatile tool for studying lipid phase behavior. The technique is attractive for fundamental biophysical studies as well applications because of its simplicity, flexibility, and ability to work with very small amounts of material crucial for biomedical studies. Further progress hinges on the understanding of the mechanism, by which a surface-acoustic technique such as QCM, senses lipid phase changes. Here, we use a custom-built instrument with improved sensitivity to investigate phase behavior in solid-supported lipid systems of different geometries (adsorbed liposomes and bilayers). We show that we can detect a model anesthetic (ethanol) through its effect on the lipid phase behavior. Further, through the analysis of the overtone dependence of the phase transition parameters, we show that hydrodynamic effects are important in the case of adsorbed liposomes, and viscoelasticity is significant in supported bilayers, while layer thickness changes make up the strongest contribution in both systems.
authors.affiliation: Institute of Physical Chemistry, Clausthal University of Technology, 38678 Clausthal-Zellerfeld, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Peschel
authors.affiliation: Institute of Physical Chemistry, Clausthal University of Technology, 38678 Clausthal-Zellerfeld, Germany.
authors.forename: Arne
authors.initials: A
authors.lastname: Langhoff
authors.affiliation: Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Eva
authors.initials: E
authors.lastname: Uhl
authors.affiliation: Institute of Physical Chemistry, Clausthal University of Technology, 38678 Clausthal-Zellerfeld, Germany.
authors.forename: Aruna
authors.initials: A
authors.lastname: Dathathreyan
authors.affiliation: Institute of Physical Chemistry, Clausthal University of Technology, 38678 Clausthal-Zellerfeld, Germany.
authors.forename: Susanne
authors.initials: S
authors.lastname: Haindl
authors.affiliation: Institute of Physical Chemistry, Clausthal University of Technology, 38678 Clausthal-Zellerfeld, Germany.
authors.forename: Diethelm
authors.initials: D
authors.lastname: Johannsmann
authors.affiliation: Institute of Functional Interfaces (IFG), Karlsruhe Institute of Technology (KIT), Hermann-von Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Ilya
authors.initials: I
authors.lastname: Reviakine
mesh_terms: D000327:Adsorption; D001703:Biophysics; D008051:Lipid Bilayers / Q000737:chemistry*; D008081:Liposomes / Q000737:chemistry; D044367:Phase Transition; D058525:Quartz Crystal Microbalance Techniques; D013696:Temperature
chemical_list: D008051:Lipid Bilayers; D008081:Liposomes