Microchannel electrophoresis

Wang, Y., Lin, Q., and Mukherjee, T., System-oriented dispersion models of general-shaped electrophoresis microchannels. Lab on a Chip 2004, 4, 453-463. 

Medintz, I.L., Berti, L., Emrich, C.A., Tom, J., Scherer, J.R., and Mathies, R.A., Genotyping energy-transfer-cassette-labeled short-tandem-repeat amplicons with capillary array electrophoresis microchannel plates. Clinical Chemistry, Al, 1614-1621,2001. 

Scherer, J.R. et al.. High-pressure gel loader for capillary array electrophoresis microchannel plates. 

Many practical/commercial microfluidic systems use a combination of integrated and modular approaches for systems assembly. In these cases, portions of the system, such as capillary electrophoresis microchannels with integrated electrodes or microsensors with integrated... 

Many practical/commercial microfluidic systems use a combination of integrated and modular approaches for systems assembly. In these cases, portions of the system, such as capillary electrophoresis microchannels with integrated electrodes, or microsensors with integrated punps and valves, may be combined with a modular approach towards the optics or other microfluidic elements. Such combinations of integrated and modular systems can be very effective resulting in the best of both worlds for a microfluidic system. 

Polymers have come a long way from parkesine, celluloid and bakelite they have become functional as well as structural materials. Indeed, they have become both at the same time one novel use for polymers depends upon precision micro-embossing of polymers, with precise pressure and temperature control, for replicating electronic chips containing microchannels for capillary electrophoresis and for microfluidics devices or micro-optical components. 

Rossier, IS Schwarz, A Reymond, F Ferrigno, R Bianchi, F Girault, HH, MicroChannel Networks for Electrophoretic Separations, Electrophoresis 20, 727, 1999. 

Protein toxins such as botulism, staphylococcal enterotoxin B, or ricin can be separated with gas or liquid chromatography, electrophoresis, or a combination. The pChemLab (Sandia National Laboratories Albuquerque, NM) series of instruments includes a hand-held Bio Detector. Proteins in the sample are labeled with fluorescent tags, and nanoliter volumes of samples are separated by microchannels etched into a glass chip. The separation occurs as the sample moves through the channels and identification is based on retention times. The analyses can be completed within 10 min. 

Unlike capillary electrophoresis, wherein absorbance detection is probably the most commonly utilized technique, absorbance detection on lab-on-a-chip devices has seen only a handful of applications. This can be attributed to the extremely small microchannel depths evident on microchip devices, which are typically on the order of 10 pm. These extremely small channel depths result in absorbance pathlengths that seriously limit the sensitivity of absorbance-based techniques. The Collins group has shown, however, that by capitalizing on low conductivity non-aqueous buffer systems, microchannel depths can be increased to as much as 100 pm without seeing detrimental Joule heating effects that would otherwise compromise separation efficiencies in such a large cross-sectional microchannel [38],... 

An alternative to DNA chips is to miniaturize DNA sequencing and analysis machinery. Using nanoliter droplets of fluid passing through microchannels built by photolithographic techniques of computer chip construction, these nanolaboratories may be the size of a credit card but able to cleave DNA and conduct PCR reactions, gel electrophoresis, and sequence determinations.435 436... 

P. Mela, A. van der Berg, Y. Fintschenko, E.B. Cummings, B.A. Simmons and B. J. Kirby, The zeta potential of cyclo-olefin polymer microchannels and its effects on insulative (electrodeless) dielectrophoresis particle trapping devices, Electrophoresis, 26 (2005) 1792-1799. 

K. Wang and X.-H. Xia, Microchannel-electrode alignment and separation parameters comparison in microchip capillary electrophoresis by scanning electrochemical microscopy, J. Chromatogr. A, 1110 (2006) 222-226. 

Mohamadi et al. [96] reported online preconcentration of human serum albumin (HSA) and its immunocomplex with a monoclonal antibody on-chip coupled to isotachophoresis. The sample injection, preconcentration, and separation were carried out continuously and controlled by a sequential voltage switching program. Preconcentration was carried out with on-chip nondenaturing gel electrophoresis in methylcellulose solution. Furthermore, the authors applied this method for immunoassay of HSA. The separation of HSA and its immunocomplex was achieved in 25 seconds in 1 cm of the microchannel with induced fluorescence detection at 7.5 pM. 

Another variation of SCCE is field-inversion electrophoresis. A sample (e.g., DNA) was passed back and forth within a short length of a microchannel. Using an alternating potential (600 V of several Hz) applied over an 8-mm channel, this method can provide a similar resolution to that of a significantly longer micro-channel. The inverting field serves to disrupt DNA alignment (reptation) with the electric field and hence recovers the size-dependent separation [651],... 

Mizukami, Y., Rajniak, D., Rajniak, A., Nishimura, M., A novel microchip for capillary electrophoresis with acrylic microchannel fabricated on photosensor array. Sensors Actuators B 2002, 81, 202-209. 

Shi, Y.N., Anderson, R.C., High-resolution single-stranded DNA analysis on 4.5 cm plastic electrophoretic microchannels. Electrophoresis 2003, 24, 3371-3377. 

Bianchi, F., Wagner, F., Hoffmann, P., Girault, H.H., Electroosmotic flow in composite microchannels and impUcations in microcapUlary electrophoresis systems. Anal. Chem. 2001, 73(4), 829-836. 

Henry, A.C., Waddell, E.A., Shreiner, R., Locascio, L.E., Control of electroosmotic flow in laser-ablated and chemically modified hot imprinted poly(ethylene tereph-thalate glycol) microchannels. Electrophoresis 2002, 23, 791-798. 

McReynolds, J.A., Edirisinghe, P., Shippy, S.A., Shah and sine convolution Fourier transform detection for microchannel electrophoresis with a charge coupled device. Anal. Chem. 2002, 74, 5063-5070. 

Liu, J., Tseng, K., Garcia, B., Lebrilla, C.B., Mukerjee, E., Collins, S., Smith, R., Electrophoresis separation in open microchannels. A method for coupling electrophoresis with MALDI-MS. Anal. Chem. 2001, 73, 2147-2151. 

Shi et al. [98] introduced a pressurized capillary array system to simultaneously load 96 samples into 96 sample wells of a radial microchannel array electrophoresis microplate for high-throughput DNA sizing (Figure 13). As a result, 96 samples were analyzed in less than 90 s per microplate, demonstrating the power of microfabricated devices for large-scale and high-performance nucleic acid characterization. 

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