AVS 45th International Symposium
    Biomaterial Interfaces Group Tuesday Sessions
       Session BI-TuM

Paper BI-TuM5
Stabilizing Supported Lipid Bilayers for Biomaterial Applications

Tuesday, November 3, 1998, 9:40 am, Room 326

Session: Biosensor-Biology Interface
Presenter: O. Dannenberger, University of Washington
Authors: O. Dannenberger, University of Washington
M. Boeckl, University of Washington
J.A. Bassuk, University of Washington
P.L. Valint, Bausch & Lomb
T. Sasaki, University of Washington
V. Vogel, University of Washington
Correspondent: Click to Email
Supported phospholipid bilayers are promising biomembrane model systems.@footnote 1@ Our special interest is to extend their application to investigate the interactions of cells with specific recognitions sites on synthetic surfaces. Bilayers are ideally suited to stabilize and expose cell receptors and membrane anchored proteins. The fluid character of supported bilayers further allows cells to spatially reorganize recognitions sites. As one major drawback of lipid bilayers is their instability we have assembled phospholid (PL) bilayers on a smooth hydrogel cushion and partially crosslinked the inner layer to the cushion and the layers themselves. The hydrogel mimics the cytoskeletal network that stabilizes the lipid membranes in living cells. HEMA was selected as the major polymer constituent due to its biocompatibility. The PL bilayers were formed using Langmuir Blodgett and Schäfer techniques. The hydrogels were investigated with AFM and angle-resolved XPS, the mono- and bilayers were studied with fluorescence and Brewster angle microscopy. We covalently linked our inner layer to the reactive groups provided on the polymer cushion. While partial linkage stabilized the inner leaflet it still exhibits a high membrane fluidity since direct interactions with the solid substrate are prevented. Bifunctional lipid-like surfactants were used to improve the stability of the outer PL leaflet through layer-to-layer crosslinking. In addition we will present the results of the attachment and spreading behavior of endothelial cells on our model surfaces. @FootnoteText@ @footnote 1@E. Sackmann, Science 271 (1996), 43-48.