Fabrication of microfluidic systems

Stjernstrom, M., Roeraade, J., Method for fabrication of microfluidic systems in glass. J. Micromech. Microeng. 1998, 8, 33-38. 

As it was mentioned earlier, a much larger range of micro/nanofabrication tools are utilized in the design and fabrication of micro/nanotransducers than applied in the fabrication of microfluidic systems. Standard photolithography as described above is only one of the many techniques used. Three examples will be described here the fabrication of freestanding transducers, UV-photolithography with lift-off technique for preparation of interdigitated ultramicroelectrode arrays (IDUAs), and more traditional techniques for microtransducer preparations. 

McDonald JC, Duffy DC, Anderson JR, Chiu DT, Wu H, Schueller OJ, et al. Fabrication of microfluidic systems in poly(dimethylsiloxane). Electrophoresis 2000 21 27-40. 

The most widely used material for fabrication of microfluidic systems, and hence also microfluidic cell culture chips, is PDMS, which in many systems is utilized in combination with glass. PDMS is fabrication wise well suited for prototyping, whereas it is not in the same degree amenable to mass reproduction. A new emerging trend is, however, fabrication using thermoplastic polymers, such as pol5miethylmethacrylate (PMMA), cyclic olefin copolymer (COC) and polycarbonate (PC), which can be used for... 

The final step in PCSL fabrication of microfluidic systems is removal of the sacrificial material to yield clean, smooth microchannel inner surfaces. Paraffin wax PCSL is removed by heating the microdevice to 85°C and applying vacuum to a reservoir in the PMMA cover piece to aspirate the liquid PCSL (Figure 51.2h). Nonpolar organic solvents such as hexane or cyclohexane can be used subsequently to dissolve and remove residual sacrificial material from inside the channel. With... 

Lin CH, Lee GB, Lin YH, Chang GL (2001) A fast prototyping process for fabrication of microfluidic systems on soda-lime glass. J Micromech Microeng ll(6) 726-732... 

Polydimethylsiloxcme is a versatile material with properties excellent for fabrication of microfluidic systems. The polymer is accessible emd inexpensive. It can reproduce masters with high accuracy md can be molded at low temperatures, enabling rapid prototyping of complex 3D structmes. Native PDMS is hydrophobic but its smface cm be ejisily modified. Particular attention should be p ud to complementary methods of chemical md topographical patterning of PDMS surface, and blending the polymer with nanoscale materials. 

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