Passive droplet sorting using viscoelastic flow focusing

摘要: We present a study of passive hydrodynamic droplet sorting in microfluidic channels based on intrinsic viscoelastic fluid properties. Sorting is achieved by tuning the droplets' viscous and properties relative to continuous oil phase achieve positive or negative lateral migration toward high low shear gradients channel. In presence weakly behavior, droplets with viscosity ratio, κ, between 0.5–10 were found migrate gradient near channel walls. For all other κ-values, Newtonian fluids, would at centerline. It was also that for strongly fluids interfacial tension, edge even κ-values lower than 0.5. The resulting bi-directional different allows size-independent sorting. Still, their efficiencies are dependent size, elasticity, viscosity, deformability, overall rates. Based these findings, we demonstrate >200 Hz frequencies >100 fold enrichment factors without need actively sense and/or control active mechanisms. Using 6.25 cPs, discrimination 1 cPs 5 aqueous 0.2 0.8 respectively.