Fabricated microfluidic devices

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,... 

Zhu et al. [76] designed and fabricated microfluidic devices on polymethylmethacrylate (PMMA) substrates for electrochemical analysis applications using an improved UY-LIGA process. The microchannel structures were transferred from a nickel mold onto the plastic plates by the hot embossing... 

The soft lithography method was developed for rapidly and inexpensively fabricating microfluidic devices with channels >20 pm width using... 

Sacrificial Layer Fabricated Microfluidic Devices 51.2.2.1 Silica and Glass Materials... 

In this entry, bulk micromachining techniques for fabricating microfluidic devices in silicon and glass materials are summarized. The details of the fabrication characteristics and fabrication protocols are described. 

Material Properties and Fabrication fii many applications in the literature, plastics, rather than pure polymers, are used to fabricate microfluidic devices. Plastics can contain a number of additives that impact on their processing and shelf life, and these should be considered. These additives may include fillers (e.g., mica, talc, and calcium carbonate). 

McDonald JC, Whitesides GM (2002) Poly(dimethyl-siloxane) as a material for fabricating microfluidic devices. Acc Chem Res 35(7) 491—499... 

Poly(dimethylsiloxane) (PDMS) is a well-known hydrophobic polymer with higher repellency for water than PS crosslinked siUcone elastomers (WCA = 112° for a smooth film) are commonly used for fabricating microfluidic devices. But forming solid fibers comprised solely of linear PDMS is not possible, due to its low glass transition temperature. Instead of using linear homopolymer PDMS, Ma et al. [21] electrospun fibers of poly(styrene-b-dimethylsiloxane) block copolymers blended with 23.4 wt% homopolymer polystyrene (PS-PDMS/PS) from a solution in a mixed solvent of THF and DMF. The resultant fiber mat, with fiber diameters in the range of 150-400 nm, exhibited a WCA of 163° and a hysteresis of 15°. An illustration of water droplets beaded up on such a mat is provided in Fig. 3. A PS mat of similar fiber diameter and porosity exhibited a WCA of only 138°. The difference was attributed to the lower surface tension of the PDMS component, combined with its spontaneous segregation to the fiber surface. X-ray photoelec-... 

Surface modification of PDMS has been used to retard swelling in organic solvents, which is particularly important for fabricating microfluidic devices and for some types of lithography. ... 

Various methods have been presented in the literature to fabricate microfluidic devices. One of the most widely used are those made from poly(dimethylsiloxane) (PDMS) gels [8,10]. The materials for these devices are relatively inexpensive and they can be made with established soft lithography processes. This approach also has the potential to form complicated and intricate flow patterns. The soft lithography process is robust and reproducible, which allows replicating flows in different devices that have the same design. 

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