Microfluidic interface

The common theme in these microfluidic valving systems is the requirement of a vacuum or pressure pump/compressor that is used to actuate the pneumatic lines that are interfaced with the on-chip valves. These pneumatic lines, in turn, are usually controlled individually using computer-operated solenoid valves with the corresponding circuitry and manifolds. Various tubing can be used to connect each solenoid valve to the corresponding microfluidic interface. Interfacing to the device can be accomplished through a variety of means, which are not discussed here. Interested readers should refer to the cited works that are particularly relevant to their own research. 

Atencia J, Beebe DJ (2005) Controlled microfluidic interfaces. Nature 437 648-655... 

Chen et al. [7] have developed a CE system based on a PMMA electrophoretic microchip with an easy sample introduction interface. One side of the PMMA chip was sharpened to fabricate a sharp inlet tip, allowing rapid and reproducible sample introduction into CE microchip devices coupled to contactless conductivity detection. The new microfluidic interface relies... 

J. Atencia, D.J. Beebe Controlled microfluidic interfaces. Nature, 2005,437, 648-655. 

J. Atenda, D. J. Beebe, Controlled microfluidic interfaces. Nature 2005,437, 648. 

Jebrail, M.J., Sinha, A., Vellucci, S., Renzi, R.F., Ambriz, C., Gondhalekar, C., Schoeniger, J.S., Patel, K.D., Branda, S.S. (2014) World-to-Digital-Microfluidic Interface Enabling Extraction and Purification of RNA from Human Whole Blood. Anal. Chem. 86 3856-3862. 

When elution chromatography is used in both dimensions, the valve configurations are similar for the different column combinations. However, when CE is utilized as the second dimension, other types of interfaces not based on valves have been implemented with unique advantages. These and the microfluidic implementation of sampling systems for chip-based two-dimensional separations will be discussed below. 

Taylor M.T., Belgrader P., Furman B.J., Pourahmadi F., Kovacs G.T.A., Northrup M.A., Lysing bacterial spores by sonication through a flexible interface in a microfluidic system, Anal. Chem. 2001 73 492-496. 

Fredrickson CK, Fan ZH (2004) Macro-to-micro interfaces for microfluidic devices. Lab Chip 4 526-533... 

Hansen CL, Skordalakes E, Berger JM, Quake SR (2002) A robust and scalable microfluidic metering method that allows protein crystal growth by free interface diffusion. Proc Natl Acad Sci USA 99 16531-16536 Herzig-Marx R, Queeney KT, Rebecca JJ, Schmidt MA, Jensen KF (2004) Infrared spectroscopy for chemically specific sensing in silicon-based microreactors. Anal Chem 76 6476-6483... 

Wang, C., Oleschuk, R., Ouchen, R, Fi, J., Thibault, P., and Harrison, D. J. (2000). Integration of immobilized trypsin bead beds for protein digestion within a microfluidic chip incorporating capillary electrophoresis separations and an electrospray mass spectrometry interface. Rapid Commun. Mass Spectrom. 14, 1377—1383. 

A microfluidic chip has been developed for rapid screening of protein crystallization conditions (Hansen et al., 2002) using the free interface diffusion method. The chip is comprised of a multilayer, silicon elastomer and has 480 valves operated by pressure. The valves are formed at the intersection of two channels separated by a thin membrane. When pressure is applied to the top channel it collapses... 

Fasolka MJ, Stafford CM, Beers KL (2009) Gradient and microfluidic library approaches to polymer interfaces. Adv Polym Sci DOI 10.1007/12 2009 17... 

Gradient and Microfluidic Library Approaches to Polymer Interfaces ... 

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