Supported Lipid Bilayers

Supported lipid bilayers can be created by two different methods: (i) vesicle fusion and rupture on a substrate and (ii) Langmuir-Blodgett deposition. The latter is more controlled and precise but lacks versatility. The former is more adaptable; however the process by which the complete bilayer is formed is not completely understood. Lipid vesicles adsorb and then rupture to create bilayers when they come in contact with silica surfaces. The rate that these vesicles adsorb and rupture is dependent on solution conditions including concentration of vesicles, salt concentration, temperature, and pH. In this study a Quartz Crystal Microbalance (QCM) is used to study the effects of the concentration of DMPC vesicles, made by extrusion through a membrane with 50 nm pores, on the kinetics of vesicle adsorption and bilayer formation on silica surfaces. Concentrations in the range of .1 mg/ml to 1 mg/ml were studied and showed that the rate of bilayer formation increased with vesicle concentration.