Microchip-based electrophoresis

Tian H, Brody LC, Landers JP. Rapid detection of deletion, insertion, and substitution mutations via heteroduplex analysis using capillary- and microchip-based electrophoresis. Genome Res 2000 10 1403-1413. 

The transfer of material from a microfluidic chip to the mass spectrometer can be performed on-line or off-line. Typically, a MALDI target is under high vacuum while microchip-based electrophoresis is carried out at atmospheric pressure. This difference in pressure makes on-line transfer a challenge. 

The purpose of this chapter has been two-fold. First, to highlight some of the basic methods and substrates that have been successfully utilized to create microfluidic devices. We have attempted to describe these methods, albeit at a rudimentary level, in a manner that allows for someone skilled in CE to fabricate, functionalize and execute microchip-based electrophoresis. In addition to the basic... 

Huynh, B.H., Fogarty, B. A., Martin, R.S., Lunte, S.M. (2004). On-line coupling of microdialysis sampling with microchip-based capillary electrophoresis. Anal. Chem. 76, 6440-6447. 

J. Wang, A. Ibanez, and M.P. Chatrathi, Microchip-based amperometric immunoassays using redox tracers. Electrophoresis 23, 3744—3749 (2002). 

Liu, C., Cui, D., Cai, H., Chen, X., and Geng, Z. (2006). A rigid poly(dimethylsiloxane) sandwich electrophoresis microchip based on thin-casting method. Electrophoresis 27, 2917—2923. 

Wang, J., G. Chen, M. Chatrathi, K. Shin, and A. Fujishima. Microchip capillary electrophoresis coupled with a boron-doped diamond electrode-based electrochemical detector. Anal. Chem. 75, 935-939 (2003). 

NH Chiem, DJ Harrison. Monoclonal antibody binding affinity determined by microchip-based capillary electrophoresis. Electrophoresis 19 3040-3044, 1998. 

Monoclonal antibody-binding affinity was determined by microchip-based capillary electrophoresis with LIF detection (33). The mixing was carried out off-chip, and the on-chip separations were performed in less than 60 s (Fig. 9). A Scatchard plot analysis resulted in an affinity constant for the monoclonal anti-BSA antibody to fluorescently labeled BSA (BSA ) of... 

S. M. Lunte, Carbon paste-based electrochemical detectors for microchip capillary electrophoresis/electrochemistry, Analyst, 126 (2001) 277-280. A.J. Gawron, R.S. Martin and S.M. Lunte, Fabrication and evaluation of a carbon-based dual-electrode detector for poly(dimethylsiloxane) electrophoresis chips, Electrophoresis, 22 (2001) 242-248. 

J. Wang, M. Pumera, M.P. Chatrathi, A. Rodriguez, S. Spillman, R.S. Martin and S.M. Lunte, Thick-film electrochemical detectors for poly(dimethylsiloxane)-based microchip capillary electrophoresis, Electroanalysis, 14 (2002) 1251-1255. 

Chiem, N., Harrison, D.J., Microchip-based capillary electrophoresis for immunoassays analysis of monoclonal antibodies and theophylline. Anal. Chem. 1997, 69, 373-378. 

Lichtenberg, J., Verpoorte, E., de Rooij, N.F., Sample preconcentration by field amplification stacking for microchip-based capillary electrophoresis. Electrophoresis 2001, 22(2), 258-271. 

Backhouse, C.J., Gajdal, A., Pilarski, L.M., Crabtree, H.J., Improved resolution with microchip-based enhanced field inversion electrophoresis. Electrophoresis 2003, 24, 1777-1786. 

Ro, K.W., Shim, B.C., Lim, K., Hahn, J.H., Integrated light collimating system for extended optical-path-length absorbance detection in microchip-based capillary electrophoresis. Micro Total Analysis Systems, Proceedings 5th pTAS Symposium, Monterey, CA, Oct. 21-25, 2001, 274-276. 

Salimi-Moosavi, H., Jiang, Y., Lester, L., McKinnon, G., Harrison, D.J., A multireflection cell for enhanced absorbance detection in microchip-based capillary electrophoresis devices. Electrophoresis 2000, 21(7), 1291-1299. 

Mangru, S.D., Harrison, D.J., Chemiluminescence detection in integrated postseparation reactors for microchip-based capillary electrophoresis and affinity electrophoresis. Electrophoresis 1998, 19(13), 2301-2307. 

Wolfe, K.A., Breadmore, M.C., Ferrance, J.P., Power, M.E., Conroy, J.F., Norris, P.M., Landers, J.P., Toward a microchip-based solid-phase extraction method for isolation of nucleic acids. Electrophoresis 2001, 23, 727-733. 

Sato, K, Yamanaka, M., Takahashi, H., Tokeshi, M., Kimura, H., Kitamori, T., Microchip-based immunoassay system with branching multichannels for simultaneous determination of interferon-y. Electrophoresis 2002, 23, 734-739. 

Colyer CL, Mangru SD, Harrison DJ. Microchip-based capillary electrophoresis of human serum proteins. J Chromatogr A 1997 781 271-276. 

Figure 10-4 Design of an asymmetric turn used in microchip-based capillary electrophoresis system constructed in glass.The design facilitates the maintenance of sample integrity during flow in a microchannel around a curve.The dimensions are indicated on the figure and are taken from the tops of the channels.The channels were filled with black ink for contrast (From Ramsey JD, Jacobson SC, Culbertson CT, Ramsey JM. High efficiency, two-dimensional separations of protein digests on micro fluidic devices.

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