Microchannel networks

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

Kikutani, Y, Horiuchi, T., Uchiyama, K., Hisamoto, H., Tokeshi, M., Kitamori, T, Glass microchip with three-dimensional microchannel network for 2x2 parallel synthesis. Lab. Chip 2 (2002) 188-192. 

Benninger, R. K. P., Koc, Y., Hofmann, O., Requejo-Isidro, J., Neil, M. A. A., French, P. M. W. and de Mello, A. J. (2006). Quantitative 3D mapping of fluidic temperatures within microchannel networks using fluorescence lifetime imaging. Anal. Chem. 78, 2272-8. 

Serial dilution was achieved in a PDMS microchannel network for immunoassay, as shown in Figure 10.10. Immunoassay of IgG antibodies present in HIV+ human serum was conducted. Using 1 1 dilution ratio and 10 sequential dilutions (only three are shown in Figure 10.10), a dynamic range of 210 or 1000 of the serum concentration was obtained. The HIV antigens (gp41, gpl20) were first adsorbed on a PC membrane, which was then sealed by the PDMS... 

Lee, S., Kim, Y., Metering and mixing of nanoliter liquid in the microchannel networks driven by fluorocarbon surfaces and pneumatic control. Micro Total Analysis Systems, Proceedings 5th p,TAS Symposium, Monterey, CA, Oct. 21-25, 2001. Kluwer Academic Publishers, Dordrecht, the Netherlands, 2001, 205-206. 

J.S. Rossier, A. Schwarz, F. Reymond, R. Ferrigno, F. Bianchi and H.H. Girault, MicroChannel networks for electrophoretic separations. Electrophoresis, 20 (1999) 727-731. 

In the development of lab-on-a-chip technology, a key is to develop the ability to pump the liquids and transport sample/reagent molecules as well as biological cells in a microchannel network. This can be achieved by using the electroosmotic flow and electrophoresis. Mixing of different solutions and dispensing a specified amount of one solution from one microchannel into another microchannel are important to many microfluidic chips. There are extensive research works done in these areas [1]. Furthermore, precise control of temperature is often critical to on-chip biochemical reactions. In the following the PCR lab-on-a-chip, flow cytometer lab-on-a-chip and immunoassay lab-on-a-chip will be reviewed. 

Figure 12. Illustration of the microchannel network in the multiplex immunoassay chip.

A pressure head in the line drives an even smaller flow into the microchannel network. The sample flows through a bypass channel (not shown), and plugs are injected at will from this stream. A 10 1 flow reduction is realized in this manner, all the while obtaining a representative sample. 

Inhibiting Bulk Flow in Multidimensional MicroChannel Networks... 

Jeon et al. [6] reported a microcharmel network method for generating defined concentration gradients in a microfluidic device. Solutions of different concentrations were introduced into the microfluidic device by syringe pumps at separate inlets and repeatedly mixed and split through the microchannel network, producing multiple diluted streams with predictable concentrations. These streams flowed side by side in a common chaimel and generated a soluble or... 

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