Eur. Phys. J. E 28, 211-220 (2009)
DOI: 10.1140/epje/i2008-10407-3

Diffusion in supported lipid bilayers: Influence of substrate and preparation technique on the internal dynamics

C. Scomparin¹, S. Lecuyer², M. Ferreira³, T. Charitat² and B. Tinland<sup>1

1</sup>  CINAM, CNRS UPR 3118, 13288, Marseille Cedex 09, France
²  Institut Charles Sadron, CNRS, Université Louis Pasteur, 23 Rue du Loess, BP 84047, 67034, Strasbourg Cedex 2, France
³  Campus de Sorocaba, Universidade Federal de São Carlos, CP 3031, 18043-970, Sorocaba, SP, Brazil

tinland@cinam.univ-mrs.fr

Received 21 March 2008 / Revised version 22 July 2008 / Published online 22 December 2008

Abstract

The diffusion law of DMPC and DPPC in Supported Lipid Bilayers (SLB), on different substrates, has been investigated in details by Fluorescence Recovery After Patterned Photobleaching (FRAPP). Over micrometer length scales, we demonstrate the validity of a purely Brownian diffusive law both in the gel and the fluid phases of the lipids. Measuring the diffusion coefficient as a function of temperature, we characterize the gel-to-liquid phase transition of DMPC and DPPC. It is shown that, depending on the type of substrate and the method used for bilayer preparation, completely different behaviours can be observed. On glass substrates, using the Langmuir-Blodgett deposition technique, both leaflets of the bilayer have the same dynamics. On mica, the dynamics of the proximal leaflet is slower than the dynamics of the distal leaflet, although the transition temperature is the same for both layers. Preparing bilayers from vesicle fusion in same conditions leads to more random behaviours and shifted transition temperatures.

PACS
87.16.D- - Membranes, bilayers, and vesicles.
87.14.Cc - Lipids.
87.16.dp - Transport, including channels, pores, and lateral diffusion.

Correspondence: tinland@cinam.univ-mrs.fr


© EDP Sciences, Società Italiana di Fisica, Springer-Verlag 2009

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