Here, we present a microfluidic droplet trap that takes advantage of the net Laplace pressure force generated when a droplet is differentially constricted. Mathematical simulations were first used to understand the working range of the component; followed by finite element modeling using the CFDsoftware package to further characterize the behavior of the system. Controlled release of the trapped droplets is also demonstrated through both a mechanical method and a chemical method that manipulates the total pressure exerted on the trapped droplet. The unique design of this trapping device also provides the capability for selection of a single dropletfrom a train, as well as droplet fusion.
Melinda Simon, Robert Lin, Jeffrey Fisher, and Abraham Lee. "A Laplace pressure based microfluidic trap for passive droplet trapping and controlled release" Biomicrofluidics (2012). doi:10.1063/1.3687400