AVS 53rd International Symposium
    Biomaterial Interfaces Wednesday Sessions
       Session BI-WeM

Paper BI-WeM3
Investigation and Quantification of Immobilized Protein in Crosslinked Bilayers

Wednesday, November 15, 2006, 8:40 am, Room 2014

Session: Bio-interfacial Modification and Bio-Immobilization I (Honoring Marcus Textor, ETH-Zürich for Substantial Contributions to the Field)
Presenter: R. Michel, University of Washington
Authors: R. Michel, University of Washington
V. Subramaniam, University of Arizona
S.L. McArthur, University of Sheffield, UK
E. Ross, University of Arizona
S. Saavedra, University of Arizona
D.G. Castner, University of Washington
Correspondent: Click to Email
Supported lipid bilayers are commonly used as model systems for cell studies. More recently, these layers, which are inherently unstable under ambient or ultra-high vacuum conditions, have been stabilized via cross-linking. These crosslinked bilayers have potential applications as biomedical coatings and biosensors. The detection and investigation of intercalating biomolecules is a first step towards creating artificial cell-like surfaces, and proteins are ideal model systems to study functionality in the bilayer. Recently it was shown that a common membrane protein, rhodopsin, could be reconstituted into these lipid bilayers and retain its photoactivity after cross-linking of the lipid bilayers. Secondary Ion Mass Spectrometry (SIMS) and X-Ray Photoelectron Spectroscopy (XPS) are surface sensitive techniques that yield information on the top few nanometers. We used these ultrahigh vacuum techniques to structurally characterize the lipid bilayers of redox and UV polymerized supported lipid membranes composed of 1,2-bis[10-(2',4'-hexadienoloxy)decanoyl]-sn-glycero-3-phosphocholine (bis-Sorb PC). UV-polymerized bis-Sorb PC bilayers with reconstituted rhodopsin were quantified with XPS. Angle resolved XPS revealed the protein to be located within the bilayer, and not adsorbed on top of it. SIMS was used to investigate the similarities and differences of distinct fragments from the phosphocholine lipids and the protein amino acids.