10. PiOEM

A technique that utilizes a membrane filter and plug-in tubes to remove oil and pack water-in-oil droplets for time-controlled droplet-based assays. Pictures above show the Plug-in Oil Extraction Module (PiOEM) removing oil directly from a flow-focusing droplet generator (top) and from a reinjected droplet library to form tightly packed droplets. Droplet packing was proved to be essential for extended and uniform incubation of all the individual droplets that travel through a microfluidic device. Thereafter, the droplet incubation time can be simply tuned by plugging in tubes with certain volumes, without the necessity of altering the patterns of the microchannels or flow in a microfluidic device.

Biomicrofluidics, 2021, 15, 024108