Microfluidic fabrication of monodisperse biocompatible and biodegradable polymersomes with controlled permeability.

We describe a versatile technique for fabricating monodisperse polymersomes with biocompatible and biodegradable diblock copolymers for efficient encapsulation of actives. We use double emulsion as a template for the assembly of amphiphilic diblock copolymers into vesicle structures. These polymersomes can be used to encapsulate small hydrophilic solutes. When triggered by an osmotic shock, the polymersomes break and release the solutes, providing a simple and effective release mechanism. The technique can also be applied to diblock copolymers with different hydrophilic-to-hydrophobic block ratios, or mixtures of diblock copolymers and hydrophobic homopolymers. The ability to make polymer vesicles with copolymers of different block ratios and to incorporate different homopolymers into the polymersomes will allow the tuning of polymersome properties for specific technological applications.