Microfluidic Mixer

Cobby, D., Angeli, P., Gaveiilidis, A., Mixing characteristics of T-type microfluidic mixers, J. Micromech. Microeng. 11 (2001) 126-132. 

Asahi Chemical, 9 676-677 Electrohydrodynamic-based heat exchangers, 13 269-270 Electrohydrodynamic (EHD) convection, in microfluidic mixers, 26 967 Electrokinetic flow... 

This micro mixer, named electrohydrodynamic (EHD) microfluidic mixer, comprises a simple T-channel structure (see Figure 1.5) [91]. After passing the T-junction, a bi-laminated stream is realized. Following a downstream zone for such flow establishment, a channel zone with several electrode wires on both sides of the channel is located. In this way, an electric field perpendicular to the fluid interface is generated. Thereafter, an electrode-free zone of the channel is situated for completion of the mixing initiated. 

Lim, D., Kamotani, Y., Cho, B., Mazumder, J., Takayama, S., Fabrication of microfluidic mixers and artificial vasculares using a high-brightness diode-pumped Nd YAC laser direct write method, Lab Chip 2003, 3, 318-323. 

Tracey, M. C., Cox, T. I., Davis, J. B., Microfluidic mixer employing temporally interleaved liqiuid slugs and parabolic flow, in Ramsey, J. M., van den Berg, A. (Eds.), Micro Total Analysis Systems, Kluwer, Dordrecht, 2001,141-141. 

A novel in-plane passive microfluidic mixer with modified Tesla structures,... 

Hong, C.C., Choi, J.W., Ahn, C.H., A novel in-plane passive microfluidic mixer with modified Tesla structures. Labchip 2004, 4, 109-113. 

Tsai, J.-H. Lin, L. Active microfluidic mixer and gas bubble filter driven by thermal bubble micropump. Sens. Actuators A. 2002, 97-98, 665-671. 

F.S. Ligler, A microfluidic mixer with grooves placed on the top and bottom of the channel. Lab Chip, 5 524-530 (2005). 

Gambin Y, Simonnet C, VanDelinder V, Deniz A, Groisman A (2010) Ultrafast microfluidic mixer with three-dimensional flow focusing for studies of biochemical kinetics. Lab Chip 10 598-609... 

Finally, a section summarizing the general advantages of microfluidic mixers/ reactors is presented. Although of high interest and importance, an in-depth review of microfluidic mixers in a diversity of microsystems for specific applications is not addressed since it falls out of the scope of this chapter. The reader is therefore directed to a number of excellent recent review articles on the specific subjects [9,19, 29-36]. 

In other words, it must be noted that, rather than design microfluidic mixer as just a scaled-down copy of a macroscale mixing device, they should be designed in ways that leverage the physical characteristic of the mixing in a confined space. 

Air bubbles can be introduced in a microfluidic mixer in order to enhance the mixing process. The surface of an air bubble in a liquid medium exposed to a sound field can act as a vibrating membrane. The membrane vibration causes a bulk fluid movement at the air-hquid interface. This effect, known as cavitation microstreaming, has been applied in microfluidic micromixers using a single bubble [181] (Fig. 19) or an array of bubbles [178, 179]. 

Tsai H Jr, Lin L (2002) Active microfluidic mixer and gas bubble Alter driven by thermal bubble micropump 1. Sens Actuators A Phys 97 665-671... 

Vijayendran R, Motsegood K, Beebe D, Leckband D (2003) Evaluation of a three-dimensional micromixer in a surface-based biosensorf. Langmuir 19(5) 1824-1828 Lin Y, Gerfen G, Rousseau D, Yeh S (2003) Ultrafast microfluidic mixer and freezequenching device. Anal Chem 75(20) 5381-5386... 

Lei K, Li W (2008) A novel in-plane microfluidic mixer using vortex pumps for fluidic discretization. J Assoc Lab Automation 13(4) 227-236... 

FIGURE 32.12 Premixer device, (a) An upstream microfluidic mixer splits and recombines fluids to expose cells to user-defined gradients under constant fluid flow, (b) The premixer can be designed to generate a wide variety of gradient shapes. (Adapted from Jeon, N. L., et al., NaX Biotechnol, 20, 8, 826. Copyright 2002. With permission from Macmillan Publishers Ltd.)... 

Detailed reviews of the structure, function, and mode of operation of microfluidic mixers are provided elsewhere. 

Fu LM, Yang RJ, Lin GH, Chien YS (2005) A novel microfluidic mixer utilizing electrokinetic driving forces under low switching frequency. Electrophoresis 26 1814-1824... 

Harnett CK, Templeton J, Dunphy-Guzman KA, Senousy YM, Kanouff MP (2008) Model based design of a microfluidic mixer driven by induced charge electroosmosis. Lab Chip 8 565-572... 

A simple microfluidic mixer module (Fig. 3a) was designed to generate controlled mixtures of two fluidic inputs. Buffer and FITC-dextran solutions, individually controlled by separate syringe pumps, were introduced into the microfluidic device via two inputs. 

El Moctar AO, Aubry N, Batton J (2003) Electrohydrodynamic microfluidic mixer. Lab Chip 3(4) ... 

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