Amphiphilic molecules bolaform

Small amphiphiles need not necessarily have a phospholipid-like structure with two tails and one head group. For example, bolaform (or bipolar) amphiphiles are amphiphilic molecules that contain two head groups separated by an extended hydrophobic chain. Bolaform amphiphiles form monolayer vesicles in which each amphiphile extends across the monolayer membrane, exposing both head groups to water and sheltering the hydrophobic chain from water. However, also these types of... 

With the advent of polymersomes and vesicles of other nonconventionar (i.e., not phospholipid-like) amphiphiles, numerous examples of monolayer vesicles in water have been reported. Typically, monolayer vesicles are prepared from small molecules with a hydrophobic core and two hydrophilic head groups (bolaform amphiphiles, see below) or from triblock-copolymers with two hydrophilic terminal blocks. The molecule must have a cylindrical or rectangular shape, so that it can arrange into a monolayer. 

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