title: Tethered bilayer lipid membranes on mixed self-assembled monolayers of a novel anchoring thiol: impact of the anchoring thiol density on bilayer formation.
abstract: Tethered bilayer lipid membranes (tBLMs) are designed on mixed self-assembled monolayers (SAMs) of a novel synthetic anchoring thiol, 2,3-di-o-palmitoylglycerol-1-tetraethylene glycol mercaptopropanoic acid ester (TEG-DP), and a new short dilution thiol molecule, tetraethylene glycol mercaptopropanoic acid ester (TEG). tBLM formation was accomplished by self-directed fusion of small unilamellar vesicles of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine. The influence of the dilution of the anchoring thiol molecule in the SAM on the vesicle fusion process and on the properties of the resulting tBLMs is studied. It is observed by quartz crystal microbalance that vesicle fusion is a one-step process for a pure TEG-DP SAM as well as for mixed SAMs containing a high concentration of the anchoring thiol. However, upon dilution of the anchoring thiol to moderate concentrations, this process is decelerated and possibly follows a pathway different from that observed on a pure TEG-DP SAM. Electrochemical impedance spectroscopy is used to qualitatively correlate the composition of the SAM to the electrical properties of the tBLM. In this paper we also delineate the necessity of a critical concentration of this anchoring TEG-DP thiol as a requisite for inducing the fusion of vesicles to form a tBLM.
authors.affiliation: Département de Chimie Moléculaire, UMR CNRS 5250, Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 9, France. Hajra.Basit@ujf-grenoble.fr
authors.forename: Hajra
authors.initials: H
authors.lastname: Basit
authors.forename: Angéline
authors.initials: A
authors.lastname: Van der Heyden
authors.forename: Chantal
authors.initials: C
authors.lastname: Gondran
authors.forename: Bernard
authors.initials: B
authors.lastname: Nysten
authors.forename: Pascal
authors.initials: P
authors.lastname: Dumy
authors.forename: Pierre
authors.initials: P
authors.lastname: Labbé
mesh_terms: D008051:Lipid Bilayers / Q000138:chemical synthesis / Q000737:chemistry*; D008567:Membranes, Artificial; D008958:Models, Molecular; D015394:Molecular Structure; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*
chemical_list: D008051:Lipid Bilayers; D008567:Membranes, Artificial; D013438:Sulfhydryl Compounds