Multi-Sorting of Large Particles Utilizing Microvortex Generation by High-Speed On-Chip Flow Control

Cell sorting is a fundamental technology in single cell analyses. Recently, multi-sorting, which is sorting technique to multi-outlets, has emerged to exploit multi-modal indexes of the cells. However, existing multi-sorting systems are not capable for high-throughput sorting of large ($\sim 100 \mu \mathrm{~m}$) particles. Here, we present an on-chip multi-sorting system of large particles by utilizing microvortex generations. Particularly, the generated vortex develops by engulfing the surrounding fluids and then generate large displacement within 1 ms. Thus, we can rapidly displace large particles to multi-outlets even in the case of a 1 mm wide channels whose wide width hinder to apply previous method to large particle. To demonstrate our system, we verify the regulation of vortex developments and sorting of $100-\mu \mathrm{m}$ beads. As results, we achieved to control the displacement of the vortex and obtain enough displacement to multi-sorting channel within $\mathbf{0. 6 6} \mathbf{~ m s}$. Moreover, we succeeded in sorting of $100-\mu \mathrm{m}$ beads with 4 outlets by regulating the vortex’s displacement. Therefore, our method extends the applicability of on-chip sorting technologies to large particles encompassing cell spheroids, fossil pollen and microalgae/organisms for various research fields.