Langmuir, Vol.10, No.4, 1246-1250, 1994
Self-Assembled Disulfide-Functionalized Amphiphilic Copolymers on Gold
A series of methacrylic lipids was polymerized to form amphiphilic copolymers with various amounts of 2-hydroxyethyl acrylate (HEA) and 2-(methacryloyloxy)ethylmethyl disulfide comonomers. The behavior of these polymeric lipids was investigated in monolayers both at the air-water interface and in self-assembled monolayers on gold supports. The HEA acts as a hydrophilic spacer along the polymer backbone, and improves the ability of the polymer to self-organize into ordered monolayers, while the disulfide groups act as anchors chemisorbed onto the gold surface. A combination of contact angle measurements, surface plasmon spectroscopy, and cyclic voltammetry shows that the amphiphilic copolymer monolayers are swellable in water and thus that a water layer between the support and the lipid membrane is preserved. The barrier properties of the polymer-modified electrode are improved by annealing in water as well as by increasing the spacer length.
Keywords:ORGANIZED MOLECULAR ASSEMBLIES;AQUEOUS PERMANGANATE INTERACTION;PENETRATION-CONTROLLED REACTIONS;LONG-CHAIN SURFACTANTS;MONOLAYER FILMS;STRUCTURAL CHARACTERIZATION;SOLID-SURFACES;ADSORPTION;MULTILAYERS;THICKNESS