Polymer microfluid devices

U. Attia, S. Marson, and J. Alcock, Micro-injection moulding of polymer microfluidic devices. Microfluidics and Nanofluidics, 7(1), 1-28, 2009. 

Hutchison JB, Haraldsson KT, Good BT et al (2004) Robust polymer microfluidic device fabrication via contact liquid photolithographic polymerization (CLiPP). Lab Chip 4 658-662... 

Becker H and Locascio LE (2002) Polymer microfluidic devices. Talanta 56 267-287. 

Becker, H., 2002. Polymer microfluidic devices. Talanta 56 (2), 267-287. Available at http // linkinghub.elsevier.eom/retrieve/pii/S003991400100594X. 

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. 

Hu SW, Ren X, Bachman M, Sims CE, Li GP, Allbritton NL (2002) Surface modification of poly(dimethylsiloxane) microfluidic devices by ultraviolet polymer grafting. Anal Chem 74 4117 Hunter RJ (1981) Zeta potential in colloid science. Academic Press, London Jensen KF (2001) Microreaction engineering is small better Chem Eng Sci 56 293... 

Yu, C., Davey, M. H., Svec, F, and Frechet, J. M. (2001). Monolithic porous polymer for on-chip solid-phase extraction and preconcentration prepared by photoinitiated in situ polymerization within a microfluidic device. Anal. Chem. 73, 5088-5096. 

CE chips are mainly obtained using various glass substrates, from inexpensive soda-lime glass to high-quality quartz.Various polymer materials are also used. The choice of a particular material depends on its surface properties, ease of fabrication, which can be quite different according to the material origin, disposability, and price. Microfabrication processes were recently reviewed and the reader is thus referred to dedicated literature for additional useful information on microfluidic device fabrication. ... 

Fig. 21 Representative microfluidic device and resulting data from ATRP on a chip a image of a microfluidic device (dimensions 25 mm x 75 mm) fabricated from UV curable thiolene resin between two glass slides b reaction data for ATRP of HPMA synthesized on a chip showing the correlation of flow rate (or residence time) to reaction time and resulting conversion of monomer (M) to polymer (ln([M]o/[M]) c comparison of number average molecular mass (M ) and poly-dispersity for -butyl acrylate prepared in a traditional round bottom flask ( Flask ) and on a chip ( CRP Chip ). (Reproduced with permission from [102])...

In the next step we are form the walls of the channels in the microfluidic device. A new, very special polymer is spin-coated on the substrate to the desired thickness. This polymer differs from the inexpensive photoresist because it comes into contact with the later fluid. Therefore, it should have a long stability it should not form cracks, should be stable against different chemicals and it should be hydrophilic or easily hydrophilized, because otherwise water will not run through the channel. Again a photo-sensitive material is used, but this time the later channel is photochemically modified. A perfect material to use is SU-8. For details see Refs. [450,451], This part can be washed away afterwards. 

M.J.A. Shiddiky, D.-S. Park and Y.-B. Shim, Detection of polymerise chain reaction fragments using a conducting polymer-modified screen-printed electrode in a microfluidic device, Electrophoresis, 26 (2005) 4656-4663. 

Kauppila et al. [28] developed a microfabricated heated nebulizer chip for atmospheric pressure photoionization-mass spectrometry. Various materials have been used to design and develop hyphenation of microfluidic devices and ESI-MS. These materials are photoresist SU-8 [29,30], polymers [31,32], and glassy carbon [33]. Thorslund et al. [34] developed a chip on which sample injection, separation, and ESI-emitter structures are integrated... 

Microfluidics and miniaturization hold great promise in terms of sample throughput advantages [100]. Miniaturization of analytical processes into microchip platforms designed for micro total analytical systems (/i-TASs) is a new and rapidly developing field. For SPE, Yu et al. [123] developed a microfabricated analytical microchip device that uses a porous monolith sorbent with two different surface chemistries. The monolithic porous polymer was prepared by in situ photoinitiated polymerization within the channels of the microfluidic device and used for on-chip SPE. The sorbent was prepared to have both hydrophobic and ionizable surface chemistries. Use of the device for sorption and desorption of various analytes was demonstrated [123]. 

Lahann, J., Balcells, M., Lu, H., Rodon, T., Jensen, K.F., Langer, R., Reactive polymer coatings A first step toward surface engineering of microfluidic devices. Anal. Chem. 2003, 75, 2117-2122. 

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