A microfluidic technique for generating monodisperse submicron-sized drops

Abstract

We present a route for producing monodisperse micro and nanodrops that is based on a liquid–gas phase transition occurring within a microfluidic device. A gas which is soluble in water is mixed with an insoluble one and injected into an aqueous surfactant solution, using a microfluidic device that produces monodisperse bubbles. As the soluble gas diffuses out of the bubbles, they shrink and the remaining insoluble gas condenses into drops. Their radius can be tuned over a wide range by changing the initial gas mixing ratio.