Controls on the transport of particles/cells in deterministic lateral displacement via symmetric airfoil with angle of attacks

Abstract

Deterministic lateral displacement (DLD), which is a microfluidic technique for size fractionation of particles/cells in continuous flow, has demonstrated great potential for biological and clinical applications. Growing interest in utilizing high-throughput DLD devices for practical applications, such as circulating tumor cell (CTC) separation, necessitates employing higher flow rates in these devices, leading to operating in moderate to high Reynolds number (Re) regimes. While high-Re operation with symmetric airfoils has been established, the effect of angle of attacks (AoAs) for airfoil on the DLD performance has not been characterized. Here, we present a high-Re investigation with symmetric airfoil-shaped pillars having positive and negative AoAs. The transport behavior of particles/cells is investigated with various AoAs in realistic high-throughput DLD devices. Unlike the conventional DLD device, no lateral displacement has been observed with positive 5 and 15 degree AoA configurations regardless of particle sizes. On the other hand, more lateral displacement has been seen with negative 5 and 15 degree AoA configurations. This can be attributed to growing anisotropic permeability and non-uniform distribution of streamlines between airfoils with AoAs.