Differential Sorting of Microparticles Using Spiral Microchannels with Elliptic Configurations

Abstract

Label-free, size-dependent cell-sorting applications based on inertial focusing phenomena have attracted much interest during the last decade. The separation capability heavily depends on the precision of microparticle focusing. In this study, five-loop spiral microchannels with a height of 90 µm and a width of 500 µm are introduced. Unlike their original spiral counterparts, these channels have elliptic configurations of varying initial aspect ratios, namely major axis to minor axis ratios of 3:2, 11:9, 9:11, and 2:3. Accordingly, the curvature of these configurations increases in a curvilinear manner through the channel. The effects of the alternating curvature and channel Reynolds number on the focusing of fluorescent microparticles with sizes of 10 and 20 µm in the prepared suspensions were investigated. At volumetric flow rates between 0.5 and 3.5 mL/min (allowing separation), each channel was tested to collect samples at the designated outlets. Then, these samples were analyzed by counting the particles. These curved channels were capable of separating 20 and 10 µm particles with total yields up to approximately 95% and 90%, respectively. The results exhibited that the level of enrichment and the focusing behavior of the proposed configurations are promising compared to the existing microfluidic channel configurations.

Progress of Microfluidic Continuous Separation Techniques for Micro-/Nanoscale Bioparticles

“…For example, particle separation can be precisely manipulated by designing the microchannel as a curved line, thus creates two counter-rotating flows called Dean vortices in the upper and lower halves of the channel cross-section. [ 99 ] Similar to this, Kuntaegowdanahalli et al [ 88 ] also developed inertial microfluidics for continuous particle separation in spiral microchannels. The competition between net lift and Dean drag creates a new balance that moves the particle to its equilibrium position.…”

Reconfigurable Modular Platform for Prolonged Sensing of Toxic Gases in Particle Polluted Environments

“…Such a separator is free from maintenance and could be designed as an add-on module. Passive inertia-based microfluidic particle separators are the focal point of many research groups for applications in biomedical and life science due to their low manufacturing cost, simplicity, ease of integration, and reliability [16,17].…”

Modeling of a Passive-Valve Piezoelectric Micro-Pump: A Parametric Study

“…Over the past few decades, the developments in the Micro-electro-mechanical Systems (MEMS) technology have realized the implementation of microfluidic devices to a wide range of applications such as drug delivery systems [ 1 ], micro-mixing [ 2 ] and particle manipulation [ 3 ], among others. Micro-pumps are one of the most frequently used devices, which supply the energy required to drive a fluid through microfluidic passages.…”