Collecting Cholesterol Efflux from Living Tissue using Lipid Bilayer Based Nano-architectures on Electrode Surfaces

摘要

Electrodes modified with lipid bilayer structures containing cholesterol oxidase are prepared for collecting cholesterol efflux from cell plasma membranes. Platinum electrodes are initially modified with a self-assembled monolayer of thiolipid. A vesicle fusion method is used to deposit the outer lipid leaflet on the thiolipid monolayer forming a thiolipid/lipid bilayer membrane on the electrode surface. Cholesterol oxidase spontaneously inserts into the electrode-supported lipid bilayer membrane from solution and is immobilized to the electrode surface. Cholesterol partitions into the lipid bilayer membrane from cell plasma membranes where it is oxidized by cholesterol oxidase for generation of anodic current. Electrochemical, atomic force microscopic, and quartz crystal microbalance characterizations studies of the electrode surfaces will be presented. A discussion of the potential application of this electrode in a cholesterol consuming fuel cell will also be given.