Droplet formation in a microchannel network

A method is given for generating droplets in a microchannel network. With oil as the continuous phase and water as the dispersed phase, pico/nanoliter-sized water droplets can be generated in a continuous phase flow at a T-junction. The channel for the dispersed phase is 100 μm wide and 100 μm deep, whereas the channel for the continuous phase is 500 μm wide and 100 μm deep. For given experimental parameters, regular-sized droplets are reproducibly formed at a uniform speed. The diameter of these droplets is controllable in the range from 100–380 μm as the flow velocity of the continuous phase is varied from 0.01 m s⁻¹ to 0.15 m s⁻¹.