Bursting and Reassembly of Giant Double Emulsion Drops Form Polymer Vesicles

Polymeric vesicles are excellent building blocks of synthetic compartmentalized systems such as protocells and artificial organelles. In such applications, the efficient encapsulation of materials into the vesicles is an essential requirement. However, common encapsulation techniques can be time-consuming, demand special equipment or have limited efficiency for large components, such as proteins and nanoparticles. Here, we describe a simple method to create cargo-filled polymer vesicles based on bursting and reassembly of giant double emulsion droplets (DED). Due to their large average diameter of 2 mm, DEDs eventually burst in the aqueous medium, producing polymeric film fragments. These fragments rapidly reassemble into smaller vesicles in a process involving folding, fusion and vesiculation. The daughter vesicles have an average diameter of 10 μm, representing a two-order of magnitude size reduction compared to the original DED, and can efficiently encapsulate components present in solution by entrapment of the aqueous medium during vesicle reassembly.