Microfluidic cell concentrator with a reduced–deviation-flow herringbone structure

Abstract

In this study, a microfluidic cell concentrator with a reduced-deviation-flow herringbone structure is proposed. The reduced-deviation-flow herringbone structure reduces the magnitude of deviation flow by a factor of 3.3 compared to the original herringbone structure. This structure shows higher recovery efficiency compared to the original herringbone structure for various particle sizes at high flow rate conditions. Using the reduced-deviation-flow herringbone structure, the experimental results show a recovery efficiency of 98.5% and a concentration factor of 3.4× at a flow rate of 100 ml/h for all particle sizes. An iterative concentration process is performed to achieve a higher concentration factor for 10.2-m particles and Jurkat cells. With two stages of the concentration process, we were able to achieve over 98% recovery efficiency and a concentration factor of 10-11×. Cell viability was found to be above 96% after iterative concentration. We believe that this device could be used to concentrate cells as a preparatory step for studying low-abundance cells.

Geometric structure design of passive label-free microfluidic systems for biological micro-object separation

“…Palumbo et al carried out a numerical study of a 3D helical IMF channel 134 . Other 3D simulations, such as the V-shaped groove structure, have been shown to be effective and helpful in assisting geometry optimization 189 . However, because the flowing nature becomes complicated as the Reynolds number increases, a numerical study of complex 3D structures becomes difficult.…”

“…Moreover, cell separation applications of herringbone grooves have been published. Hyun et al proposed a reduced-deviation-flow herringbone structure for cell concentration, which achieved a recovery efficiency of 98.5% 189 . Wang et al designed a microfluidic chip with double-sided herringbone microstructures to capture rare tumor cells (Fig.…”

Inertial Microfluidic Syringe Cell Concentrator

“…Although the centrifugation has been regarded as the “gold standard” for concentrating micro/nanomaterials, it may not suitable for use in resource-poor settings as the commercial centrifuge is bulky and requires electricity-powered. In addition, the centrifugation is incapable for concentrating samples with small volumes or with low concentrations due to the cell loss under a heavy centrifugal effect. − Another classic scheme for cell concentration is microfiltration, which employs micropores of specific sizes to capture the cells and remove the cell-free fluid . However, it is difficult to release the captured cells and avoid the clogging issue.…”

A passive microfluidic device for continuous microparticle enrichment

“…Specifically, because of the simple structure and good performance, inertial focusing has attracted great attention since first observed by Segre and Silberberg . Microchannels used for the inertial focusing include the straight channel , the straight channel with three dimensional (3D) microstructures on top or bottom walls , the straight channel with expansion‐contraction cavity arrays , the spiral channel and the curved serpentine channel . For instance, subjected to the inertial lift force, microparticles were focused in four‐point attractor positions in square microchannel while they were focused in two or three laterally positioned streams in a rectangular microchannel with appropriate aspect ratio and Reynolds number ( Re ) .…”

“…However, the multiple particle equilibrium positions would produce problems for separation, extraction and downstream sensing . In straight microchannel with 3D microstructure or expansion‐contraction cavity arrays , microparticle were focused based on the balance between the inertial lift force and the drag force induced by the secondary flow. While 3D microstructures, such as herringbone structure , grooves and diagonal ridges were utilized to generate the secondary flow on the cross section, it is complicated to fabricate these 3D structures on top or bottom walls of microchannel.…”