Figure 1
From: Rapid purification of sub-micrometer particles for enhanced drug release and microvesicles isolation
Particle separation using HiDFF. (a) Schematic illustration of the HiDFF separation principle in a two-inlet, two-outlet spiral microchannel. Particles introduced at the outer wall migrate laterally towards the inner wall under the influence of Dean vortices and the Dean drag forces (FD). As the particles migrate along the channel top and bottom, they experience size-dependent, wall-induced lift forces (FWL) that push larger particles further away from the surfaces. (b) Subtle differences in the particle z-position (along the height) lead to a size-based transient innermost distance (Dinner) at the inner wall, which can be exploited for small particle separation with superior resolution. (c) Size fractionation of polydispersed drug-loaded MPs using HiDFF to purify sub-micrometer particles for enhanced drug delivery. (d) Single-step isolation of circulating extracellular microvesicles/MPs in blood for rapid vascular health profiling. (e) Composite high speed images at the channel bottom (~5 μm height) indicate increasing axial flow speed with particle size. (f) Fluid simulation (COMSOL) of the transverse Dean flow patterns of the channel top half inner region. Color bar represents the Dean velocity magnitude (in m s−1). Empirically determined Dinner positions of 1, 2 and 3 μm beads are indicated (drawn to scale).
