Fabrication of Polymersomes using Double Emulsion Templates in Stamped Microfluidic Devices

We present a versatile technique for fabricating polymersomes in glass-coated stamped microfluidic devices. We use templates comprised of double emulsions with a shell of block copolymers dissolved in organic solvents. The double emulsions direct the assembly of amphiphilic diblock copolymers into polymersomes during evaporation of the organic solvents. Our device consists of a single cross junction to make the core phase and two additional cross junctions to make the shell phase; this geometry allows us to inject two separate organic solvents to form the shell phase, greatly facilitating the formation of the polymersomes; by tuning their ratio of these two solvents, we control the rate at which the solvent mixture is evaporated. Moreover, this geometry also prevents fouling of the microfluidic device due to adsorption on the microchannel walls of poorly dissolved copolymers, allowing polymersomes to form.