Micromixing Chip

Microfluidic mixer Micromixer Micromixing chip Passive mixer... 

Figure 2.7 Silicon micromixer chip for high mass flow rates 20 x 20 mm footprint.

Abonnenc, M Dayon, L., Perruche, B Lion, N., Girault, H.H. (2008) Electrospray Micromixer Chip for On-line Derivatization and Kinetic Studies. Anal. Chem. 80 3372-3378. 

Govindan CK (2002) An improved process for the preparation of benzyl-n-vinyl carbamate. Org Process Res Dev 6 74-77 Gunther A, Jensen KF (2006) Multiphase microfluidics from flow characteristics to chemical and materials synthesis. Lab Chip 6 1487-1503 Gunther A, Jhunjhunwala M, Thalmann M, Schmidt MA, Jensen KF (2005) Micromixing of miscible liquids in segmented gas liquid flow. Langmuir 21 1547-1555... 

Bertsch, A., Heimgartner, S., Cousseau, P., Renaud, P., Static micromixers based on large-scale industrial mixer geometry, Lab Chip 2001, 1, 56-60. 

Hinsmann, P., Frank, J., Svasek, P., Harasek, M., Lendl, B., Design, simulation and application of a new micromixing device for time resolved infrared spectroscopy of chemical reactions in solution, Lab Chip 2001, 1, 16-21. 

A micromixer (100 pL) was constructed on a quartz chip with multiple small channels (5 pm wide) intersecting 45° with the main channels (27 pm wide) (see Figure 3.39). EOF flow of two solutions containing different concentrations of fluorescein was initiated to achieve mixing based on the principle of eddy diffusion after splitting in the smaller channels [493]. 

The activity of [i-galactosidasc (P-Gal) was studied on a quartz chip using a static micromixer to mix the enzyme and substrate on the ms time scale. Inhibition by phenylethyl-P-D-thio-galactoside was also studied [1048]. In another report, the enzyme P-Gal was assayed on a chip in which P-Gal would convert a substrate, resoruhn-P-D-galactopyranoside (RBG), to resoruhn to be detected fluorescently [1049]. By varying the substrate concentrations and monitoring the amount of resoruhn by LIF, Michaelis-Menten constants could be determined. In addition, the inhibition constants of phenylethyl-P-D-thiogalactoside, lactose, and p-hydroxymercuribenzoic acid to the enzyme P-Gal were determined [1049]. 

Hessel, V., Numerical simulation of polymerization in interdigital multilamination micromixers. Lab Chip 5(9) (2005) 966-973. 

Micromixers have been developed for flows ranging from < 1 mL h up to 10 000 L h At the low flow range, only single elements of the micromixer are required. These are often used in integrated systems for credit card sized fluidic chips [65]. For flows > 1 L h microstructured mixers are used for process intensification in pilot- and conventional-scale applications [65]. 

The first prototype micromixer was a roughly 1 mm thick silicon plate with the dimensions of ca. 17 X 30 mm (Fig. 15.4). The hrst trivial task to be solved was how to introduce reagents and organic solvents into this micromixer. The first approach was to glue a hypodermic needle onto the silicon chip. The resulting construction was fairly fragile and had to be stabilized by a polymer cast. 

One of the simple ways to achieve active mixing is to induce a pressure field disturbance. Active micromixers relying on this strategy have been reported from different authors [43, 156-159], Deshmuck et al. [156, 157] proposed a T-junction microfluidic chip with an integrated micropump that alternatively drives and stops the flow within the microdevice to create a segmented flow. 

Zhang C, Xing D, Li Y (2007) Micropumps, microvalves, and micromixers within PCR microfluidic chips advances and trends. Biotechnol Adv 25(5) 483-514... 

Melin J, Gimenez G, Roxhed N, Wijngaart W, Stemme G (2004) A fast passive and planar liquid sample micromixer. Lab Chip 4(3) 214—219... 

Liu R, Yang J, Pindera M, Athavale M, Grodzinski P (2002) Bubble-induced acoustic micromixing. Lab Chip 2(3) 151-157... 

Ahmed D, Mao X, Shi J, Juluri B, Huang T (2009) A millisecond micromixer via single-bubble-based acoustic streaming. Lab Chip 9(18) 2738-2741. http //dx.doi.org/10.1039/ B903687C... 

This microvalve approach, providing a variable pressure source by means of a chip-embedded microchannel, is a simplified on-chip pressure-control scheme that minimizes the need for peripheral equipment and electronic components, which in any case are difficult to integrate into a microfluidic chip. Apt application of this method can realize many desirable micropump [75], micromixer [76], and microplatform [77] functions such as those illustrated in Fig. 7. 

Rosenfeld C, Serra C, Brochon C et al (2008) Influence of micromixer characteristics on polydispersity index of block copolymers synthesized in continuous flow microreactors. Lab Chip 8 1682-1687... 

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