Microchip use

Arenkov, P., Kukhtin, A., Gemmell, A., Voloshchuk, S., Chupeeva, V., and Mirzabekov, A. (2000). Protein microchips Use for immunoassay and enzymatic reactions. Anal. Biochem. 278, 123-131. 

FIGURE 5.10 The image of a microchip used in 2D MEKC-CE described in Ramsey et al. (2003). Note that injections are made at valve 1 (VI) for the first-dimension MEKC separation. Solute is sampled into the CE system at V2. Other designations are provided in the original reference. This figure is used by permission of the American Chemical Society. 

Roddy, E.S., Lapos, J.A., Ewing, A.G. (2003). Rapid serial analysis of multiple oligonucleotide samples on a microchip using optically-gated injection. J. Chromatogr. A 1004, 217-224. 

Sakai-Kato, K., Kato, M., Ishihara, K. and Toyo-oka, T. (2004) An enzyme immobilization method for integration of biofunctions on a microchip using a water-soluble amphiphilic phospholipid polymer having a reacting group. Lab on a Chip, 4, 4—6. 

Wallenborg, S. R. and C. G. Bailey. Separation and detection of explosives on a microchip using micellar electrokinetic chromatography and indirect laser-induced fluorescence. Anal. Chem. 72, 1872-1878 (2000). 

Separation and detection of p-aminophenol and ascorbic acid has also been evaluated in Topas microchips using different end-channel amperometric detectors. Thus, platinum- and gold-wire, screen-printed carbon electrode and gold film have been used as working electrodes [77]. 

It should also be noted that the Method part of the software integrates all the data concerning the nature of the test to perform, the reagent used, the references of the microchip used, the experimenter s name as well as the date and time of the assay. All these data are then automatically stored in the final report concerning the experiments run with this protocol, which greatly facilitates the discovery of possible experimental errors as well as the traceability of the obtained results. 

Faure et al. [22] described nanoelectrochromatography on poly (dimethyl)-siloxane microchips using organic monolithic stationary phases for analysis of derivatized catecholamines. Surface modification of the PDMS material was carried out by UV-mediated graft polymerization. The efficiency of the unit was ascertained by measuring theoretical plates, which were 200,000 per meter. Furthermore, the authors optimized the separation by using pinched and electrokinetic modes at different applied potential of l.OkV/cm (Fig. 7.6) and 30kV/cm (Fig. 7.7) for the pinched and electrokinetic... 

Figure 8.22. Capillary electrophoresis on a chip, (a) Schematic of the microchip used for PCR amplification and electrophoresis. The direction of arrows indicate injection (I) and separation (S). (b) Electrophoretic microchip with multiple PCR chambers.

FIGURE 4.16 Image of the glass microchip used for 2D chemical separations. The separation channel for the OCEC (first dimension) extends from the first valve VI to the second valve V2. The CE (second dimension) extends from the second valve V2 to the detection point y. Reservoirs for sample (S), buffer 1 and 2 (Bl, B2), sample waste 1 and 2 (SW1, SW2), and waste (W2) are positioned at the terminals of each channel. The arrows indicate the detection points in the OCEC channel (x) and CE channel (y) [333]. Reprinted with permission from the American Chemical Society. 

FIGURE 10.21 (a) Cross-sectional view of the microchip, heating element, and the thermocouples. (b) Schematic of the microchip used for on-chip reactions, separations, and post-column labeling. The fluid reservoirs are (1) substrate, (2) enzyme or DTT, (3) buffer, (4) sample waste, (5) NDA, and (6) waste [1058]. Reprinted with permission from Elsevier Science. 

Munaka, T., Kanai, M., Abe, H., Fujiyama, Y., Sakamoto, T., Mahara, A., Yamay-oshi, A., Nakanishi, H., Shoji, S., Murakami, A., In situ cell monitoring on a microchip using time-resolved fluorescence anisotropy analysis. Micro Total Analysis Systems 2003, Proceedings 7th pTAS Symposium, Squaw Valley, CA, Oct. 5-9, 2003, 283-286. 

Neurotransmitters have also been detected on microchips using electrochemical detection, eliminating the need for on-chip reactions or derivitization. Amperometric detection, a current change when an analyte passes the detection electrodes, was demonstrated on a microchip for the determination of dopamine concentrations in standard solutions [10], The microdevice developed in this... 

Figure 4 Separation of 100 pM amino acid mixture consisting of (1) alanine, (2) valine, (3) glutamine, and (4) tryptophan in an unmodified PMMA microchip using indirect, contact conductivity detection. Electrophoretic conditions 3-s electroki-netic injection time =150 V/cm for the electrophoresis. (Reprinted with permission from Ref. 20.)...

Huang Z, Jin L, Sanders JC, Zheng Y, Dunsmoor C, Tian H, et al. Laser-induced fluorescence detection on multichannel electrophoretic microchips using micro-porcessorembedded acousto-optic laser beam scanning. IEEE Trans Biomed Eng 2002 49 859-866. 

Arenkov P, Kukhtin A, Gemmell A et al (2000) Protein microchips use for immunoassay and enzymatic reactions. Anal Biochem 278 123-131... 

The technique of isoelectric focusing has proven to be a useful tool in protein chemistry, and this too has been adapted to the microchip. Using 7-cm-long channels in glass microchips (200 [Xm wide and 10p,m deep) mixtures of Cy5-labeled peptides can be focused in less than 30 seconds. This same procedure has also been applied to plastic microchips made from EMMA by laser ablation and shown to focus mixtures of peptides labeled with rhodaraine green. Results for this type of microchannel isoelectric focusing are available in less than 5 minutes compared with traditional techniques that take over 1 hour. 

Dill K, Montgomery DD, Ghindihs AL, Schwarzkopf KR. 2004. Immunoassays and sequence-specific DNA detection on a microchip using enz3mie amphfied electrochemical detection. J Biochem Biophys Methods 59 181-187. 

The microchip used was similar to the chip shown in Figure 2, which has three main channels, five reservoirs and a detection cell. As model analytes, dopamine and catechol were separated and detected using the permanganate CL system on the microchip. The samples were electrokinetically injected into the double-T cross section and separated in the separation channel, and then oxidized by CL reagent which was delivered by a home-made micropump to produce light in the detection cell. The EOF can be coupled with the micropump flow. The detection limits for... 

Fig. 17 Schematic representation of a capillary electrophoresis microchip using a confo-cal epiluminescence microscope as an ultrasensitive detection system to monitor the analytes separated on the separation channel of a CE microchip. (Adapted from Refs. 68 and 454.)...

Fig. 6 (a) Microchip used for preconcentration and the subsequent electrophoretic separation of the preconcentrated proteins using SDS-PAGE. (b) Microscopic image of preconcentrator-injector channels, (c) Cross-section through injector and preconcentrator channels. Reproduced, with permission, from [120]... 

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