When amphiphilic molecules are placed in an aqueous solution, their hydrophobic tails avoid water while their hydrophilic heads interact with it. This drives the formation of various nanostructures:
Micelles: Spherical structures where hydrophobic tails are tucked inside, away from water, while hydrophilic heads face outward. Vesicles: Bilayered spheres that can encapsulate aqueous solutions inside, useful for drug delivery. Bilayers: Planar structures forming the basis of cell membranes and synthetic lipid bilayers.