Experimental and theoretical study on the microparticle trapping and release in a deformable nano-sieve channel

Abstract

Deformable microfluidics may be potentially used in cell manipulation, optical sensing, and imaging applications, and have drawn considerable scientific interests in the recent past. The excellent tunability of deformable microfluidic devices can provide controllable capture, deposition, and target release. We demonstrated a one-dimensional nano-sieve device to capture microparticles from suspensions. Size-selective capturing and release of micro-and nanoparticles was achieved by simply adjusting the flow rate. Almost all the microparticles were trapped in the nano-sieve device at a flow rate of 20 μl min −1 . Increasing the flow rate induces a hydrodynamic deformation of the roof of the compliant device and allows most of the microparticles to pass through the channel. We also established a theoretical model based on computational fluid dynamics to reveal the relationship of the hydrodynamically induced deformation, channel dimensions, and capture efficiency that supports and rationalizes the experimental data. We have predicted the capture efficiency of micro-and nanoparticles in a nano-sieve device with various geometries and flow rates. This study may be important to the optimization of next generation deformable microfluidics for efficient micro-and nanostructure manipulations.

Single Chlamydomonas reinhardi (C. reinhardtii) cell separation from bacterial cells and auto-fluorescence tracking with a nano-sieve device

“…As shown in Fig. 1d , the C. reinhardtii cells are uniformly patterned in a parabolic shape (dashed white line), which is in agreement with our deformation theoretical model (Chen et al, 2019).…”

“…We previously introduced a deformable nano-sieve device that can selectively trap microparticles by controlling the hydrodynamic deformation of the shallow channel (Chen et al, 2019; Chen et al, 2020). Furthermore, the captured targets can be easily released by inducing a large deformation of the adaptable channel roof.…”

Single Chlamydomonas reinhardtii cell separation from bacterial cells and auto‐fluorescence tracking with a nanosieve device

“…As shown in Fig. 1D, the C. reinhardtii cells are uniformly patterned with a parabolic profile on their deposition boundary (dashed white line), which is in agreement with a previously investigated theoretical model for channel deformation [28].…”

“…A deformable nanosieve device was previously introduced that can selectively trap microparticles by controlling the hydrodynamic deformation of the shallow channel [28,29]. The height of the channel changes based on the flow rate of the solution applied since the channel deforms under hydrodynamic pressure [28]. The theoretical model for this behavior was presented in our previous work, which details the change in height of the channel under various flow rates [28].…”

“…The height of the channel changes based on the flow rate of the solution applied since the channel deforms under hydrodynamic pressure [28]. The theoretical model for this behavior was presented in our previous work, which details the change in height of the channel under various flow rates [28]. Generally, the channel continues to expand to greater heights under higher flow rates causing cells of larger sizes to pass through.…”