Formation of Bilayer Lipid Membranes with Microfluidic Devices

Abstract

Membrane proteins play very important roles in cells. They are also useful in various industrial fields, including drug discovery, and highly sensitive ion-channel-based biosensors. Here, I describe our two approaches toward membrane protein chips: an array of membrane proteins on (1) planar lipid bilayers and (2) giant vesicles. First, a highly reproducible method was developed for planar lipid bilayer reconstitution. Planar lipid bilayers are formed at apertures by flowing lipid organic solution and buffer alternately into an integrated microfluidic channel. Using this technique, multiple lipid bilayers are formed simultaneously, and channel currents through peptide ion channels were recorded. Second, I describe a method for the preparation of lipid vesicles inspired by forming soap bubbles from a soap film. In our “blowing” method, lipid vesicles are blown out of the pre-formed bio-functional planar lipid membrane, directly encapsulating ejected materials. We believe that these devices are useful for an efficient and rapid analysis of singlespecies-specific membrane proteins.