title: Minor effects of bulk viscosity on lipid translational diffusion measured by the excimer formation technique.
abstract: We have investigated the effect of bulk viscosity on lipid translational diffusion using the excimer formation technique. In contrast to a study by Vaz et al. (1987), performed with the fluorescence recovery after photobleaching technique, we observed only a minor decrease of less than a factor of two for pyrene labelled phosphatidylcholine in glycerinated phosphatidylcholine bilayer membranes compared to an aqueous dispersion. Even the diffusion of pyrene labelled gangliosides with an oligosaccharide head-group that protrudes from the membrane surface is not strongly restricted by the increased bulk viscosity. We conclude that the viscosity of the fluid bounding the lipid bilayers is of minor importance for the diffusion of membrane lipids.
authors.affiliation: Institut für Biochemie, Technische Hochschule Darmstadt, Federal Republic of Germany.
authors.forename: M
authors.initials: M
authors.lastname: Ollmann
authors.forename: A
authors.initials: A
authors.lastname: Robitzki
authors.forename: G
authors.initials: G
authors.lastname: Schwarzmann
authors.forename: H J
authors.initials: HJ
authors.lastname: Galla
mesh_terms: D005732:Gangliosides; D008051:Lipid Bilayers; D008962:Models, Theoretical; D008968:Molecular Conformation; D010713:Phosphatidylcholines; D013050:Spectrometry, Fluorescence; D014783:Viscosity
chemical_list: D005732:Gangliosides; D008051:Lipid Bilayers; D010713:Phosphatidylcholines