Modification of tethered bilayers by phospholipid exchange with vesicles

Published

February 27, 2013

Author(s)

David J. Vanderah, Rima Budvytyte, Mindaugas Mickevicius, Gintaras Valincius, Frank Heinrich

Abstract

Phosphatidylcholine and cholesterol exchange between vesicles and planar tethered bilayer lipid membranes (tBLMs) was demonstrated from electrochemical impedance spectroscopy (EIS), fluorescence microscopy (FM), and neutron reflectometry (NR) data. Cholesterol is incorporated into the tBLMs, as determined by the functional reconstitution of the pore forming toxin -hemolysin (EIS data), attaining cholesterol concentrations nearly equal to that in the donor vesicles. Using fluorescently-labeled lipids and cholesterol, FM indicates that the vesicle-to-tBLM exchange is homogeneous for the lipids but not for cholesterol. NR data with perdeuterated lipids indicates lipid exchange asymmetry with two lipids exchanged in the outer leaflet for every lipid in the inner leaflet. NR and EIS data further show different exchange rates for cholesterol (t¿ 4 h). This work lays the foundation for the preparation of robust, lower-defect, more biologically relevant tBLMs by essentially combining the two methods of tBLM formation – rapid solvent exchange and vesicle fusion – and likely could be extended to the transfer of proteins from vesicles/eukaryotic cells.

Citation

Langmuir

Volume

29

Issue

13

Pub Type

Journals

Download Paper

DOI Link

Keywords

TETHERED BILAYER MEMBRANES, SELF-ASSEMBLED MONOLAYERS, VESICLES

Citation

Vanderah, D. , , R. , , M. , , G. and , F. (2013), Modification of tethered bilayers by phospholipid exchange with vesicles, Langmuir, [online], https://doi.org/10.1021/la304613a (Accessed December 21, 2024)