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In this work, we apply theoretical, computational and experimental fluid dynamics to characterize hydrodynamics micro-vortices formation in the dispersed phase at the flow-focusing microfluidic droplet generation junction. This interfacial hydrodynamic method can be exploited to trap cells inside the micro-vortices and later release them in a one-to-one manner to achieve high efficiency single-cell encapsulation inside droplets. This passive trap and release mechanism is controlled by the distance between the closed vortex streamline and the liquid-liquid interface (dgap) and, thus, fundamental understanding of the micro-vortices and parameters affecting their formation, trajectory and magnitude is necessary to achieve effective one-to-one encapsulation.
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Overcoming Double-Poisson Limitation for Co-encapsulation in Droplets through Hydrodynamic Close Packing of Cells
The study of cell-cell interaction in high-throughput is critically important in many biological systems, including oncology, immunology, and tissue engineering. However, the passive co-encapsulation of one type A cell and one type B cell per single droplet, termed 1-1-1 encapsulation, has been dictated by double Poisson distribution, which yields only ~5% efficiency with common cell loading density. Such low efficiency makes it impractical for biological analyses at scale. Here, we demonstrate a passive 1-1-1 co-encapsulation microfluidic device that leverages close packing of cells with hydrodynamic sheath flow to achieve over two-fold improvement compared to the double Poisson model.
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- Award ID(s):
- 1841509
- PAR ID:
- 10390303
- Date Published:
- Journal Name:
- Proceedings from the 26th International Conference on Miniaturized Systems for Chemistry and Life Sciences (MicroTAS 2022)
- Page Range / eLocation ID:
- 1-2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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