title: Phospholipid/cholesterol/decanethiol mixtures for direct assembly of immunosensing interfaces.
abstract: In this work, a simple yet robust method to prepare lipid-based biosensing interfaces on gold using common lipids (a phospholipid and cholesterol) and an alkanethiol is reported. The lipids were carefully chosen to tailor the biophysical properties of the bilayer. The simplicity of the method relies on the incorporation of a small percentage of decanethiol in the lipid vesicles for a direct formation of a thiol-linked supported lipid bilayer, which is advantageous in several respects. It prevents the use of specially synthesized thiolipids and preserves the natural fluidity and dynamics of the lipids. As a consequence the whole arrangement is extremely stable regarding ionic strength changes and solution flow during surface plasmon resonance experiments. Moreover, we show that this interface is very effective on suppressing the nonspecific adsorption of proteins on the surface, and enables the covalent attachment of the recognition antibody. The subsequent detection of specific interaction toward antigen was monitored in real-time by SPR and confirmed by ellipsometric measurements. This lipid-based biosensing platform is versatile and can be adapted to the biorecognition reaction of interest.
authors.affiliation: Centro de Química e Bioquímica. Faculdade de Ciências, Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisboa, Portugal.
authors.forename: I
authors.initials: I
authors.lastname: Almeida
authors.affiliation: Centro de Química e Bioquímica. Faculdade de Ciências, Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisboa, Portugal.
authors.forename: J T
authors.initials: JT
authors.lastname: Marquês
authors.affiliation: Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: W
authors.initials: W
authors.lastname: Liu
authors.affiliation: Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Niu
authors.affiliation: Centro de Química e Bioquímica. Faculdade de Ciências, Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisboa, Portugal.
authors.forename: R F M
authors.initials: RF
authors.lastname: de Almeida
authors.affiliation: Institute of Mechanics, Chinese Academy of Sciences, Beijing 100190, China.
authors.forename: G
authors.initials: G
authors.lastname: Jin
authors.affiliation: Centro de Química e Bioquímica. Faculdade de Ciências, Universidade de Lisboa, Edifício C8, Campo Grande, 1749-016 Lisboa, Portugal. Electronic address: anaviana@fc.ul.pt.
authors.forename: A S
authors.initials: AS
authors.lastname: Viana
mesh_terms: D015374:Biosensing Techniques; D002784:Cholesterol / Q000737:chemistry*; D018625:Microscopy, Atomic Force; D010743:Phospholipids / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D020349:Surface Plasmon Resonance
chemical_list: D010743:Phospholipids; D013438:Sulfhydryl Compounds; D002784:Cholesterol
keywords: Antibody covalent coupling; Immunosensors; Inhibition of nonspecific adsorption; Planar hybrid supported lipid bilayers; Surface plasmon resonance; Thiol–gold linkages