title: Protein diffusion in a bicontinuous microemulsion: inducing sub-diffusion by tuning the water domain size.
abstract: We study the diffusion of an enhanced green fluorescent protein (GFP+) in bicontinuous sugar-surfactant based microemulsions. The size of the water domains in such systems is controlled by changes of the oil-to-water ratio. Hence, microemulsions allow to produce confinement effects in a controlled way. At high water content the protein is found to exhibit Fickian diffusion. Decreasing the water domain size leads to a slowing down of the protein diffusion and sub-diffusive behavior is obtained on the scale observed by fluorescence correlation spectroscopy. Further decrease of the water domain size finally nearly fixes the GFP+ in these domains and forces it to increasingly follow the breathing mode of the microemulsion matrix.
authors.affiliation: Universität Bayreuth, Physikalische Chemie I, Universitätsstr. 30, D-95447 Bayreuth, Germany.
authors.forename: Ralph
authors.initials: R
authors.lastname: Neubauer
authors.affiliation: Universität Bayreuth, Physikalische Chemie I, Universitätsstr. 30, D-95447 Bayreuth, Germany and Universität Bielefeld, Physikalische und Biophysikalische Chemie, Universitätsstr. 25, D-33615 Bielefeld, Germany. thomas.hellweg@uni-bielefeld.de.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Höhn
authors.affiliation: Universität Bayreuth, Physikalische Chemie I, Universitätsstr. 30, D-95447 Bayreuth, Germany.
authors.forename: Martin
authors.initials: M
authors.lastname: Dulle
authors.affiliation: Laboratoire Léon Brillouin, CE Saclay, Gif sur Yvette, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Lapp
authors.affiliation: Universität Bielefeld, Physikalische und Biophysikalische Chemie, Universitätsstr. 25, D-33615 Bielefeld, Germany. thomas.hellweg@uni-bielefeld.de.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schulreich
authors.affiliation: Universität Bielefeld, Physikalische und Biophysikalische Chemie, Universitätsstr. 25, D-33615 Bielefeld, Germany. thomas.hellweg@uni-bielefeld.de.
authors.forename: Thomas
authors.identifier: http://orcid.org/0000-0002-2394-5846
authors.initials: T
authors.lastname: Hellweg