Microfluidic device for controlled dilution and sorting of droplets by electrokinetic driving forces

A droplet-based microfluidic device has been developed for the controlled dilution and sorting of droplets by means of electrokinetic forces. Neutral and cationic dyes have been tested in order to demonstrate the dilution efficiency. In addition, yeast cells and latex beads were successfully enclosed in droplets in a controlled manner. Experiments results demonstrate that even under rapid concentration changes, the rate of production and size of the droplets remained constant. Following the generation of the diluted droplets, the remaining net surface charge allows them to be sorted according to their dilution.