title: Atomic force microscopy observation of highly arrayed phospholipid bilayer vesicle on a gold surface.
abstract: Tapping mode atomic force microscopy (TM-AFM) imaging of a phospholipid bilayer vesicle (liposome) immobilized on a gold surface was performed to investigate morphologies of the electrode surfaces produced through application of three different sample preparation methods. We compared both methods from a morphological viewpoint using TM-AFM images. Liposomes, composed of zwitterionic and anionic phospholipids, were prepared by extrusion. Results indicate that the surface with immobilized L1-liposome, which was fabricated by the amino coupling method, seemed to form large amounts of aggregated or fused liposomes. In contrast, L2-liposome-containing 1-octadecanthiol that was directly attached on the gold surface using thiol-gold binding force was immobilized as a uniform surface topology without liposome aggregation. Finally, we attempted to arrange individual L3-liposome, prepared by mixing zwitterionic and anionic phospholipids, onto the gold layer by electron-beam (e-beam) lithography technique. A third method, L3-liposome formation on the sensor surface, is greatly anticipated for biosensor applications.
authors.affiliation: Institute for Scientific and Industrial Research, Osaka University, 8-1 Mihogaoka, Ibaraki, Osaka 567-0047, Japan.
authors.forename: HoSup
authors.initials: H
authors.lastname: Jung
authors.forename: JongMin
authors.initials: J
authors.lastname: Kim
authors.forename: JongWan
authors.initials: J
authors.lastname: Park
authors.forename: SangEun
authors.initials: S
authors.lastname: Lee
authors.forename: HeaYeon
authors.initials: H
authors.lastname: Lee
authors.forename: Ryoichi
authors.initials: R
authors.lastname: Kuboi
authors.forename: Tomoji
authors.initials: T
authors.lastname: Kawai
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000032:analysis / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D008051:Lipid Bilayers / Q000032:analysis / Q000737:chemistry*; D008422:Materials Testing; D008839:Microelectrodes; D018625:Microscopy, Atomic Force / Q000379:methods; D008968:Molecular Conformation; D049329:Nanostructures / Q000032:analysis / Q000737:chemistry* / Q000648:ultrastructure*; D010743:Phospholipids / Q000032:analysis / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D008051:Lipid Bilayers; D010743:Phospholipids; D006046:Gold