Selective arrangement of vesicles on artificial lipid membrane by biotin-avidin interaction

Abstract

Lipid bilayers suspended over microwells on Si substrates are promising platforms for nanobiodevices that mimic cell membranes. Using the biotin-avidin interaction, we have succeeded in selectively arranging vesicles on the freestanding region of a lipid bilayer. When ternary lipid mixtures of saturated lipid, unsaturated lipid, and cholesterol are used, they separate into liquid-order (L o) and liquid-crystalline (L α ) domains. A freestanding lipid bilayer prefers the L α -phase over the L o-phase because of the difference in their flexibility. In addition, the type of biotinylated lipid determines whether it is localized in the L α -phase domain or the L o-phase domain. As a result, the biotinylated unsaturated lipids localized in the L α -phase domain aggregate in the freestanding lipid bilayer, and vesicles labeled with biotin selectively bind to the freestanding lipid bilayer by the biotin-avidin interaction. This technique helps to introduce biomolecules into the freestanding lipid bilayer of nanobiodevices via vesicles.