A Digitally Controllable Polymer-Based Microfluidic Mixing Module Array

Abstract

This paper presents an integrated digitally controllable microfluidic system for continuous solution supply with a real-time concentration control. This system contains multiple independently operating mixing modules, each integrated with two vortex micropumps, two Tesla valves and a micromixer. The interior surface of the system is made of biocompatible materials using a polymer micro-fabrication process and thus its operation can be applied to chemicals and bio-reagents. In each module, pumping of fluid is achieved by the vortex micropump working with the rotation of a micro-impeller. The downstream fluid mixing is based on mechanical vibrations driven by a lead zirconate titanate ceramic diaphragm actuator located below the mixing chamber. We have conducted experiments to prove that the addition of the micro-pillar structures to the mixing chamber further improves the mixing performance. We also developed a computer-controlled automated driver system to control the real-time fluid mixing and concentration regulation with the mixing module array. This research demonstrates the integration of digitally controllable polymer-based microfluidic modules as a fully functional system, which has great potential in the automation of many bio-fluid handling processes in bio-related applications.

A Laminar Flow-Based Microfluidic Tesla Pump via Lithography Enabled 3D Printing

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Push/Pull Inequality Based High-Speed On-Chip Mixer Enhanced by Wettability

“…The important key words of this study are “flow in microfluidic channel”, “vibration input”, “surfactant”, and “experiment”. However, there are many studies discussing the flow in a microfluidic channel through the use of a “simulation” [ 7 , 11 , 31 , 35 , 36 , 37 , 38 , 39 , 40 , 41 ]. The closest study from the viewpoint of overlapping key words is that conducted by Kelder et al, who discussed the mathematical formulation of a fluid flow by considering the “vibration input” and the “surfactant” and showed various interesting “numerical simulations,” while focusing on the behavior of droplets appearing from the membrane rather than those of the fluid flow [ 31 ].…”

“…The difference between passive and active approaches is whether the vortex is generated naturally without any actuator or actively with an additional actuator. For a passive approach, there are various studies [ 6 , 7 , 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 , 16 ] in which the common strategy for generating the vortices is to mix two liquids in a microfluidic channel using a special configuration.…”

On-chip density mixer enhanced by air chamber

“…12, 044108-1 while flows are mostly laminar in an on-chip system with a low Reynolds number. One of the approaches for mixing two liquids on a chip is to merge two liquids inside one channel by breaking the layer boundaries (Hsiao et al, 2014;Lam and Li, 2012;Camesasca et al, 2006;Singh et al, 2008;Kang et al, 2008, Lin et al, 2005and Liu et al, 2008). Conventional approaches include adding bumps inside the channel or changing the shape of the channel from straight to curved.…”