Microfluidic large scale integration

Thorsen, T., Maerkl, S.J., Quake, S.R., Microfluidic large-scale integration. Science 2002, 298. 

Thorsen T, Maerkl SJ, Quake R (2002) Microfluidic large-scale integration. Science 298 580-584... 

Microfluidic large scale integration describes a microfluidic channel circuitry with chip-integrated valves based on a flexible membrane between a liquid-guiding and a pneumatic control-channel layer. The valves are closed (opened) by applying an overpressure (underpressure) on the control-channel, leading to deflection (withdrawal) of the membrane into the liquid-guiding channel. 

Based on the high elasticity of PDMS, the elementary microfluidic unit operation is a valve which is typically made of a planar glass substrate and two layers of PDMS on top of each other. One of the two elastomer layer contains the fluidic ducts while the other elastomer layer features pneumatic control channels. To realize a microfluidic valve, a pneumatic control channel crosses a fluidic duct as depicted in Fig. 9a. A pressure p applied to the control chaimel squeezes tlie elastomer into the lower layer, where it blocks the liquid flow. Because of the small size of this valve in the order of 100 x 100 pm, a single integrated fluidic circuit can accommodate thousands of valves. Comparable to developments in microelectronics, this approach is called microfluidic large scale integration (LSI) [122]. 

Some of the platforms can also be considered as multi-application platforms, which is of special interest in the field of research instrumentation. Here, portability is of less importance, and the number of multiple parameters per sample as well as programmability (potentially also during an assay run) gains impact. The microfluidic large scale integration and the droplet based electrowetting and surface acoustic waves platforms are such versatile examples. 

T. Thorsen, S. J. Maerkl and S. R. Quake, Microfluidic large-scale integration. Science, 298, 580-584 (2002). 

Theeuwes F, Yum SI (1976) Principles of the design and operation of generic osmotic pumps for the delivery of semisolid or liquid drug formulations. Annals Biomed Eng 4 343-353 Thorsen T, Maerkl SJ, Quake SR (2002) Microfluidic large-scale integration. Science 298 580-584... 

Nisisako T, Torii T (2008) Microfluidic large-scale integration on a chip for mass production of monodisperse droplets and particles. Lab Chip 8(2) 287-293... 

Yu B (2010) Microfluidic large scale integration and its application in image based microflow cytometry. MPhil Thesis, University of Waterloo... 

Melin, J. and S. R, Quake 2007. Microfluidic large-scale integration The evolution of design rules for biological automation. Ann Rev Biophys Biomol Struct 36 213-31. 

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