Rapid Fabrication of a Pumpless PDMS Microfluidic Device Using CO2 Laser Micromachining for Automated Formation of Monodisperse Water-in-Oil Droplets

To form monodisperse water-in-oil droplets in a fully automated fashion, we fabricated a pumpless microfluidic device consisting of top and bottom polydimethylsiloxane slabs. All microstructures required for droplet formation were directly patterned on the surfaces of two polydimethylsiloxane slabs using CO2 laser micromachining, facilitating rapid fabrication of the current device. This device formed uniformly sized droplets (a coefficient of variation for droplet diameters of <4%) at a rate of similar to 220 droplets/s.

Automated summary

A pumpless microfluidic device was fabricated to produce monodisperse water-in-oil droplets in a fully automated manner. The device, consisting of polydimethylsiloxane (PDMS) slabs with patterned microstructures created by CO2 laser micromachining, allowed for rapid fabrication. The device achieved a high production rate of uniformly sized droplets (coefficient of variation for droplet diameters <4%).