| Abstract
| - Although fluid lipid films have been used widely in biosensing devices, they lack the high stabilitydesired for technological implementation because the noncovalent forces between the constituent lipidsare relatively weak. In this work, polymerized, planar supported lipid bilayers ((poly)PSLBs) composedof diene-functionalized lipids have been prepared and characterized. Several parameters relating (poly)PSLB structure and stability to observations made in studies of polymerized bilayer vesicles were examined,including a comparison of UV photopolymerization and redox-initiated radical polymerization, the numberand location of the polymerizable moieties in the lipid monomer, and a comparison to PSLBs producedwith diacetylene lipids. Redox-initiated polymerization of films composed of bis-substituted diene lipidswith at least one polymerizable moiety located near the acyl terminus produced dried PSLBs that werehighly uniform and stable. All other conditions yielded PSLBs that contained a high density of defects afterdrying, including those formed from diacetylene lipids. In most cases, defect formation is attributed todesorption of unreacted monomers or low molecular weight polymers when the film was passed throughthe air/water interface. Studies on highly stable (poly)PSLBs doped with nonpolymerizable lipids showedthat 40−80% of the dopants are retained when the film is dried. Thus to ensure quantitative lipid retentionupon PSLB removal from water, all of the lipid monomers must be covalently anchored to the polymernetwork.
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