Microchips electrophoresis

Electroosmotic flow (EOE) is thus the mechanism by which liquids are moved from one end of the sepai ation capillai y to the other, obviating the need for mechanical pumps and valves. This makes this technique very amenable to miniaturization, as it is fai simpler to make an electrical contact to a chip via a wire immersed in a reservoir than to make a robust connection to a pump. More important, however, is that all the basic fluidic manipulations that a chemist requires for microchip electrophoresis, or any other liquid handling for that matter, have been adapted to electrokinetic microfluidic chips. 

HPLC with microchip electrophoresis. Capillary RPLC was used as the first dimension, and chip CE as the second dimension to perform fast sample transfers and separations. A valve-free gating interface was devised simply by inserting the outlet end of LC column into the cross-channel on a specially designed chip. Laser-induced fluorescence was used for detecting the FITC-labeled peptides of a BSA digest. The capillary HPLC effluents were continuously delivered every 20 s to the chip for CE separation. 

Yang, X.H., Zhang, X.M., Li, A.Z., Zhu, S.Y., Huang, Y.P (2003). Comprehensive two-dimensional separations based on capillary high-performance liquid chromatography and microchip electrophoresis. Electrophoresis 24, 1451-1457. 

Jacobson, S. C., and Ramsey, J. M. (1995). Microchip electrophoresis with sample stacking. 

Kato, M., Gyoten, Y., Sakai-Kato, K., and Toyo oka, T. (2003). Rapid analysis of amino acids in Japanese green tea by microchip electrophoresis using plastic microchip and fluorescence detection.. Chromatogr. A 1013, 183 — 189. 

Ludwig, M., and Beider, D. (2003). Coated microfluidic devices for improved chiral separations in microchip electrophoresis. Electrophoresis 24, 2481—2486. 

Xu, Z., Nakamura, Y., and Hirokawa, T. (2005). Impact of reservoir potentials on the analyte behavior in microchip electrophoresis computer simulation and experimental validation for DNA... 

Tachibana, Y., Otsuka, K., Terabe, S., Arai, A., Suzuki, K., and Nakamura, S. (2003). Robust and simple interface for microchip electrophoresis-mass spectrometry.. Chromatogr. A 1011, 181-192. 

Jacobson, S. C., R. Hergenroder, L. B. Koutny, R. J. Warmack, and J. M. Ramsey, Effects of injection schemes and column geometry on the performance of microchip electrophoresis devices. Anal. Chem., 66, 1107-1113 (1994). 

Wang, J., M. Pumera, M. P. Chatrathi, A. Escarpa, R. Konrad, A. Griebel, W. Domer, and H. Lowe. Towards disposable lab-on-a-chip Poly(methylmethacrylate) microchip electrophoresis device with electrochemical detection. Electrophoresis 23, 596-601 (2002). 

Zeng, Fl.-L., Shen, FI., Nakagama, T., and Uchiyama, K., Rroperty of ionic liquid in electrophoresis and ots application in chiral separation on microchips. Electrophoresis, 28, 4590-4596,2007. 

Recently, microchip electrophoresis was applied to GAG analysis using ethidium bromide as a fluorescent dye. In particular, separation times were reduced to 150 s, while sensitivity remained comparable to that of conventional electrophoretic methods that rely on cellulose acetate membranes [47]. 

Matsuno Y, Kinoshita M, Kakehi (2005) Fast analysis of glycosaminoglycans by microchip electrophoresis with in situ fluorescent detection using ethidium bromide. J Pharm Biomed Anal 37 429-436... 

J. Palmer, N. J. Munro, and J. P. Landers, A Universal Concept for Stacking Neutral Analytes in Micellar Capillary Electrophoresis, Anal. Chem. 1999, 71, 1679 J. Palmer, D. S. Burji, N. J. Munro, and J. P. Landers, Electrokinetic Injection for Stacking Neutral Analytes in Capillary and Microchip Electrophoresis, Anal. Chem. 2001, 73, 725 J. P. Quirino, S. Terabe, and... 

J.G.A. Brito-Neto, J.A.F. da Silva, L. Blanes and C.L. do Lago, Understanding capacitively coupled contactless conductivity detection in capillary and microchip electrophoresis. Part 1. Fundamentals, Electroanalysis, 17 (2005) 1198-1206. 

P. Kuban and P.C. Hauser, Effects of the cell geometry and operating parameters on the performance of an external contactless conductivity detector for microchip electrophoresis, Lab Chip, 5 (2005) 407-415. J.G.A. Brito-Neto, J.A.F. da Silva, L. Blanes and C.L. do Lago, Understanding capacitively coupled contactless conductivity detection in capillary and microchip electrophoresis. Part 2. Peak shape, stray capacitance, noise, and actual electronics, Electroanalysis, 17 (2005) 1207-1214. 

J. Lichtenberg, N.F. de Rooij and E. Verpoorte, A microchip electrophoresis system with integrated in-plane electrodes for contactless conductivity detection, Electrophoresis, 23 (2002) 3769-3780. 

Y. Du, J. Yan, W. Zhou, X. Yang and E. Wang, Direct electrochemical detection of glucose in human plasma on capillary electrophoresis microchips, Electrophoresis, 25 (2004) 3853-3859. 

D. J. Fischer, W.R. Vandaveer IV, R.J. Grigsby and S.M. Lunte, Pyro-lyzed photoresist carbon electrodes for microchip electrophoresis with dual-electrode amperometric detection, Electroanalysis, 17 (2005) 1153-1159. 

N. E. Hebert, W.G. Ruhr and S.A. Brazill, A microchip electrophoresis device with integrated electrochemical detection A direct comparison of constant potential amperometry and sinusoidal voltammetry, Anal. Chem., 75 (2003) 3301-3307. 

A.-J. Wang, J.-J. Xu, Q. Zhang and H.-Y. Chen, The use of poly(dime-thylsiloxane) surface modification with gold nanoparticles for the microchip electrophoresis, Talanta, 69 (2006) 210-215. 

Y. Liu, J.A. Vickers and C.S. Henry, Simple and sensitive electrode design for microchip electrophoresis/electrochemistry, Anal. Chem., 76 (2004) 1513-1517. 

C.D. Garcia and C.S. Henry, Direct determination of carbohydrates, amino acids, and antibiotics by microchip electrophoresis with pulsed amperometric detection, Anal. Chem., 75 (2003) 4778-4783. 

C.D. Garcia, B.M. Dressen, A. Henderson and C.S. Henry, Comparison of surfactants for dynamic surface modification of poly(dimethylsiloxane) microchips, Electrophoresis, 26 (2005) 703-709. 

Microchip electrophoresis I electrochemistry systems for analysis of nitroaromatic explosives... 

Analysis of nitrated organic explosives by microchip electrophoresis... 

This chapter demonstrated that microchip electrophoresis reached maturity and is appropriate for analysis of nitrated explosives. However, to create easy-to-operate field portable instruments for pre-blast explosive analysis would require incorporation of world-to-chip interface, which would be able to continuously sample from the environment. Significant progress towards this goal was made and integrated on-chip devices which allow microfluidic chips to sample from virtually any liquid reservoir were demonstrated [25,31]. 

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