LIPID MONOLAYER AND BILAYER SUPPORTED ON POLYMER-FILMS - COMPOSITE POLYMER-LIPID FILMS ON SOLID SUBSTRATES

We report the deposition of lipid monolayers and bilayers on polyacryl amide films deposited by radical chain reaction onto solid substrates in aqueous solutions. Polymer films of Various degrees of monomer dens ity and cross-linking are prepared. Lateral diffusion and fluorescent probe permeation measurements yield insight into the continuity of the lipid layers and show that monolayers exposed to air are much less se nsitive towards polymer heterogeneities than bilayers below water, whi ch is explained in terms of the wetting laws. The diffusion studies of lipid and lipopeptide probes yield absolute values of the frictional coefficients between the lipid layer and the polymer films and allow o ne to estimate the surface viscosity of the polymer film. The potentia l applications of supported membranes on soft thin polymer films for t he preparation of biofunctionalized surfaces or biocompatible receptiv e surfaces for biosensors are discussed.