Team:TU Eindhoven/Microfluidics/Cell Encapsulation Device

Cell Encapsulation Device

The cell encapsulation device (Figure 3 and Figure 4) is based on the droplet device shown earlier. However this time there are two continuous phases (co-flow) that come together at the first flow-focusing cross junction. One containing cells and the other containing a PEG solution. At this point the two continuous phases will create a laminar flow next to each other. At the second flow-focusing cross junction, encapsulation of cells will take place according to the same principle as in the droplet device. Once droplets are formed they pass through a bumpy mixer [1]. This will ensure that the content is homogeneously distributed in the droplet.

Next the droplets will pass through a droplet chamber. This chamber is designed to hold up to a thousand droplets evenly distributed. The 12 pillars inside the chamber prevent the chamber from collapsing. After the flows are stabilized and droplets are formed they can be trapped in the chamber. In the end the inlets and outlet can be cauterized to prevent the droplets from escaping. Now the droplets can simply be analyzed with a microscope.

For an AutoCAD design of this microfluidic cell encapsulation device, download here. Design by Leroy Tan, Boris Arts & Rafiq Lubken.

Figure 3. From top to bottom: oil inlet, continuous phase 2 inlet (containing PEG-DBCO), continuous phase 1 inlet (containing E. coli) and outlet.

Figure 4. The first flow-focusing cross junction is at the point where the orange channels and the yellow channel are coming together. The second flow-focusing cross junction is at the point where the orange and red channels are coming together.

Bibliography

[1] Song H, Chen DL, Ismagilov RF. Reactions in droplets in microfluidic channels. Angew Chem Int Ed Engl. 2006;45:7336–7356.