Construction and electrochemistry of Langmuir-Blodgett films of fullerene lipid composite/hybrid materials

Studies of the electrochemistry of Langmuir-Blodgett (LB) films of C ₇₀/artificial lipids including tridodecylmethylammonium bromide (3C ₁₂N ⁺Br ^-, 1), didodecylphosphate (2C ₁₂PO ₄H, 2), and dioleoylphosphatidylcholine (DOPC, 3) and of LB films of a fullerene lipid (4) bearing triple alkyl chains on a C ₆₀ moiety on electrodes were carried out in aqueous media. Stable Langmuir monolayers of fullerene C ₇₀/artificial lipid composites and the fullerene lipid (4) were formed at the air-water interface and these monolayers were transferred onto electrodes as LB films. Here, we focus on the importance of cationic matrix lipid films to the facile electrochemistry of C ₇₀ embedded in a LB film of cationic lipids on an electrode in aqueous media. On the basis of the electrolyte dependence and the charge dependence of the matrix lipids, a possible electron-transfer mechanism of the C ₇₀/artificial lipid LB film-modified electrodes is presented. Electrochemistry of a LB film of 4 was also obtained in an aqueous medium. We demonstrate that the introduction of the chemistry of lipid bilayer membranes to the LB films of fullerenes guides us toward the construction of fullerene/lipid bilayer devices.