Figure 1.

Droplet microfluidic techniques reviewed and integrated in this study

A. Droplet generation device for single-cell encapsulation with two inlets for introducing two different sample fluids. B. Droplet generation chip with only one inlet for the sample fluid. Both droplet generators can produce droplets at rates of 250–350 droplets/s and effectively encapsulate single cells at concentration of 0.1 cells/droplet. C. Automatic droplet sorting chip based on fluorescence. The high voltage signal applied to the terminals creates a dielectrophoretic effect, resulting in droplet sorting. The electrodes conducting the signal are colored in red and black. This picture also shows the interrogation window, where fluorescence inspection is taking place by shining each droplet with a laser and capturing the emitted light with a PMT sensor. D. Passive droplet merging device capable of merging droplets at 200 droplets/s. Note. All the channels in the insets colored in blue are filled with the oil phase, whereas channels colored in orange carry the sample fluids’ aqueous phases. The designs of these devices were adapted from [6], [12]. Panels A–C were adapted by permission from Mazutis and colleagues [6]. PMT, photomultiplier tube; HVA, high voltage amplifier.