Self-Assembly of Temperature Sensitive Unilamellar Vesicles by a Blend of Block Copolymers in Aqueous Solution

A self-assembled unilamellar vesicle, which can be used as a drug delivery system, was easily and simply fabricated using a blended system of Pluronic block copolymers. Controlling the hydrophilic mass fraction of block copolymers (by blending the block copolymer with a different hydrophilic mass fraction) and temperature (i.e., the hydrophobic interaction is controlled), a vesicular structure was formed. Small angle neutron scattering measurements showed that the vesicular structure had diameters of empty cores from 13.6 nm to 79.6 nm, and thicknesses of the bilayers from 2.2 nm to 8.7 nm when the hydrophobic interaction was changed. Therefore, considering that the temperature of the vesicle formation is controllable by the concentration of the blended block copolymers, it is possible for them to be applied in a wide range of potential applications, for example, as nanoreactors and nanovehicles.