Single Lipid Bilayer Deposition on Polymer Surfaces Using Bicelles

A lipid bilayer was deposited on a 3 μm diameter polystyrene (PS) bead via hydrophobic anchoring of bicelles containing oxyamine-bearing cholesteric moieties reacting with the aldehyde functionalized bead surface. Discoidal bicelles were formed by mixing dimyristoylphosphatidylcholine (DMPC), dihexanoylphosphatidylcholine (DHPC), dimyristoyltrimethylammonium propane (DMTAP), and the oxyamine-terminated cholesterol derivative, cholest-5-en-3β-oxy-oct-3,6-oxa-an-8-oxyamine (CHOLOA), in the molar ratio DMPC/DHCP/DMTAP/CHOLOA (1/0.5/0.01/0.05) in water. Upon exposure to aldehyde-bearing PS beads, a stable single lipid bilayer coating rapidly formed at the bead surface. Fluorescence recovery after photobleaching demonstrated that the deposited lipids fused into an encapsulating lipid bilayer. Electrospray ionization mass spectrometry showed that the short chain lipid DHPC was entirely absent from the PS adherent lipid coating. Fluorescence quenching measurements proved that the coating was a single lipid bilayer. The bicelle coating method is thus simple and robust, can be modified to include membrane-associated species, and can be adapted to coat any number of different surfaces.