Substrate Effects on the Formation Process, Structure and Physicochemical Properties of Supported Lipid Bilayers

Abstract

Supported lipid bilayers are artificial lipid bilayer membranes existing at the interface between solid substrates and aqueous solution. Surface structures and properties of the solid substrates affect the formation process, fluidity, two-dimensional structure and chemical activity of supported lipid bilayers, through the 1–2 nm thick water layer between the substrate and bilayer membrane. Even on SiO2/Si and mica surfaces, which are flat and biologically inert, and most widely used as the substrates for the supported lipid bilayers, cause differences in the structure and properties of the supported membranes. In this review, I summarize several examples of the effects of substrate structures and properties on an atomic and nanometer scales on the solid-supported lipid bilayers, including our recent reports.

Self-assembly of monolayered lipid membranes for surface-coating of a nanoconfined Bombyx mori silk fibroin film

“…2,3 The surface structure and properties of a solid substrate signicantly determine the selfassembly process, structure and functional activity of the supported lipid membranes. 6,7 On the other hand, due to the amphipathicity and biocompatibility of lipid molecules, lipid membranes have been regarded as one of the promising coating surfaces for biomaterials especially those with hydrophobic surfaces, in the cases of protein adsorption and immunologic rejection aer implantation. 6,7 On the other hand, due to the amphipathicity and biocompatibility of lipid molecules, lipid membranes have been regarded as one of the promising coating surfaces for biomaterials especially those with hydrophobic surfaces, in the cases of protein adsorption and immunologic rejection aer implantation.…”

Formation and fluidity measurement of supported lipid bilayer on polyvinyl chloride membrane

“…The structures and properties of substrates are crucial factors for the formation and the physical properties of SLBs. 15 There has been no report, to our knowledge, about the SLB formation directly on a PVC membrane. The lipid-containing polymers on PVC supports are the fundamental structure of the taste sensors developed by K. Toko,16,17 but the lipids are plasticized with the polymer membranes thus do not form bilayer structure.…”

“…15 After we tried various experimental parameters such the annealing temperature (4°C, 25°C and 60°C), chemical modification and treatment of the substrate (hydrophobization with hexamethyldisilazane (HMDS), thermal treatment to remove adhesive surface water layer, and hydrophilization with UV-ozone ashing), other substrate material (thermally oxidized SiO 2 /Si), and the combinations of them, we finally found that the dominant factor for the bubble formation was the thickness of the PVC/THF solution dropcast on the substrate. A transparent PVC membrane was obtained when 20 µL of the PVC/THF solution was dropcast on a 20×20 mm 2 of the Si 3 N 4 /Si substrate, or the 10 µL solution on an 8×8 mm 2 substrate (Fig.…”

“…13,14 Supported lipid bilayers (SLBs) are artificial lipid bilayer membranes existing at the interfaces between solids with hydrophilic surfaces and aqueous solutions. 11,12,15 The SLBs on solid sensing devices will be valuable as artificial biomembrane platforms for the investigation of lipids and membrane proteins in vitro.…”

“…The SLB was prepared by the vesicle fusion method. 15 Lipid vesicles, also called liposomes, are spherical lipid bilayers dispersed in aqueous solutions. On a hydrophilic surface, vesicles fuse with each other and/or rupture, then transform to planar membrane under appropriate conditions (Fig.…”