Efficient Production of Monodisperse Giant Unilamellar Vesicles by Transferring Across the W-O Interface

The monodispersity of giant unilamellar vesicles (GUVs) is important in terms of the quantitative analysis and experimental reproducibility as biomimetic microreactors. Here, we report a facile and reproducible microfluidics-based method to generate monodisperse thin-walled water-in-oil-in-water (W/O/W) droplets as a precursor of GUVs. We explored the composition of liquids and membranes for the stable transfer of monodisperse water-in-oil (W/O) droplets across the W-O laminar flow interface, and determined the condition in which W/O/W droplets with ~1 μm shell thickness are produced at 100% efficiency. We observed the dewetting phenomenon of the oil phase, which is necessary to convert the lipid-stabilized W/O/W droplets to GUVs.