Chip-based microfluidic systems

Figure 3.11 A schematic representation of a chip-based microfluidic system [20].

Klank, H., J. P. Kutter, and O. Geschke. C02-laser micromachining and back-end processing for rapid production of PMMA-based microfluidic systems. Lab on a Chip 2, 242-246 (2002). 

The approach to use chip based electroanalytical systems to monitor the dynamics of processes in living cells facilitate the possibility to integrate the detection systems to microfluidic cell culture chips. In virtue of the functional principle of such systems, cells can be cultured on the platform where detection takes place. Hence, the measurements can be conducted in an environment that has been tailor-made for proper adaptation to the requirements of the cultured cells. Furthermore, such miniaturized systems possess the capability to achieve operational automation and facilitate measurements... 

With the rapid development of cell-based microfluidic systems in the lab-on-a-chip field, ultrasonic standing wave manipulation and control of cells in microspace can be anticipated to play an increasing role in future microfluidic systems. 

Surface chemistry is also of great importance in chip-based microfluidic devices, especially in highly miniaturized and integrated systems, owing to the high surface-area-to-volume ratio. The motivations for performing surface manipulation are similar to those for classical CE. 

Microfluidic ChipShop (http //www.microfluidic-chipshop.com/) has also developed portable chip-based electrophoresis systems coupled with C D for on-site food analysis (ChipGenie edition E) [192]. Because contactless conductivity allows label-free detection, it is quite attractive to monitor the stability or the degradation products related to foodstuff. The portable instmment developed by microfluidic ChipShop comprises a box with dimensions of 190x 120x80mm (wxdxh). Basically, it consists of two parts, as shown in Figure 16.13, which are closed together and locked before running... 

Fang, Q., Wang, F.-R., Wang, S.-L., Liu, S.-S., Xu, S.-K., and Fang, Z.-L., Sequential injection sample introduction microfluidic-chip based capillary electrophoresis system, Anal. Chim. Acta, 390, 27, 1999. 

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. 

Chip-based systems that employ microfluidics have become a popular research area and a number of systems are now available commercially that utilize electrophoresis-... 

B. Zheng, J.D. Tice, L.S. Roach, and R.F. Ismagilov A Droplet-Based, Composite PDMS/Glass Capillary Microfluidic System for Evaluating Protein Crystallization Conditions by Microbatch and Vapor-Diffusion Methods with on-Chip X-Ray Diffraction. Angew. Chem. Int. Ed. 43, 2508 (2004). 

Oleschuk, R. D., L. L. Shultz-Lockyear, Y. Ning, and D. J. Harrison. Trapping of bead-based reagents within microfluidic systems On-chip solid-phase extraction and electrochromatography. Anal. Chem. 72, 585-590 (2000). 

S. Ferko, V. A. VanderNoot, J. A. A. West, R. Crocker, B. Wiedenman, D. Yee, and J. A. Fruetel, Hand-Held Microanalytical Instrument for Chip-Based Electrophoretic Separations of Proteins, Anal. Chem. 2005, 77, 435 J. G. E. Gardeniers and A. van den Berg, Lab-on-a-Chip Systems for Biomedical and Environmental Monitoring, Anal. Bioanal. Chem 2004,378, 1700 J. C. McDonald and G. M. Whitesides, Poly(dimethylsiloxane) as a Material for Fabricating Microfluidic Devices, Acc. Chem. Res. 2002,35, 491 Y. Huang,... 

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