BioMEMS applications

Future markets for biomedical microdevices for human genome studies, drug discovery and delivery in the pharmaceutical industry, clinical diagnostics, and analytical chemistry are enormous (tens of billions of U.S. dollars).In the following sections, major bioMEMS applications and microfluidics relevant to bioMEMS applications are briefly introduced. Because of the very large volume of publications on this subject, only selected papers or review articles are referenced in this entry. 

Microfluidics is the manipulation of fluids in channels, with at least two dimensions at the micrometer or submicrometer scale. This is a core technology in a number of miniaturized systems developed for chemical, biological, and medical applications. Both gases and liquids are used in micro-/nanofluidic applications, ° and generally, low-Reynolds-number hydrodynamics is relevant to bioMEMS applications. Typical Reynolds numbers for biofluids flowing in microchannels with linear velocity up to 10 cm/s are less than Therefore, viscous forces dominate the response and the flow remains laminar. 

Lee KB, Lin LW (2004) Surface micromachined glass and polysilicon microchannels using MUMPs for BioMEMS applications. Sens Actuator A lll(l) 44-50... 

Lai, S., Lee, L. J., Yu, L., KoelUng, K. W., Madou, M. J., in Micro- and nano-fabrication of polymer based microfluidic platforms for bioMEMS applications. Materials Research Society Symposium Proceedings, 17—27 (2002). 

Table 2 BioMEMS applications using pSi as part of a chip-based system...

Besides these aforementioned applications, porous silicon can also be used as part of a chip-based system, providing different functionalities. Table 2 presents those BioMEMS applications, including microfluidic applications (Abgrall and Gue 2007). 

Sandwich structures of PEG3 and polysilicon were used to create microfluidic elements by a multi-step deposition and etch process [324]. The created channels had a cross-sectional area of 70 x 4 j,m and should be used for BioMEMS applications. 

In addition to the term MEMS, categories like microoptoelectromechanical systems (MOEMS), radio-frequency MEMS (RF-MEMS), and MEMS for medical or biomedical application (BioMEMS) have been established. The market for microfabricated devices is still in its infancy and is growing with rates comparable to the first years of microelectronics. According to one market research report, the sales of microfabricated systems was 12 billion in 2004 and is expected to grow with a CAGR of 16% to 25 billion in 2009 [6]. Recent extensions of fields of application are consumer, entertainment, and homeland security. Upcoming new devices are MEMS microphones, microenergy sources, micropumps, chip coolers, and micromachined wafer probes, and this will definitely not be the end of new developments. 

S.M. Block, Making light work with optical tweezers. Nature 360, 493-495 (1992) K. Svoboda, S.M. Block, Biological applications of optical forces. Annu. Rev. Biophys. Biomem. 23, 247-285 (1994)... 

Ziaie, B., Baldi, A., Lei, M.. Gu, Y.D., and Siegel, R.A. (2004) Hard and soft micromachining for BioMEMS review of techniques and examples of applications in microfluidics and drug delivery. Advanced Drug Delivery Reviews, 56 (2), 145-172. 

Biomedical Microdevices—BioMEMS and Biomedical Nanotechnology. The Netherlands Kluwer Academic Publishers. ISSN 1387-2176. Interdisciplinary periodical devoted to all aspects of research in the diagnostic and therapeutic applications of micro-electro-mechanical systems (MEMS), microfabrication, and nanotechnology. Contributions on fundamental and applied investigations of the material science, biochemistry, and physics of biomedical microdevices are encouraged. 

BioMEMS, BioNEMS, or industrial applications requiring soft sensors, actuators, and micro or nano-scale robotic applications. 

Erickson D, Li D (2006) Microscale flow and transport simulation for electroldnetic and lab-on-chip applications. In Bashir R, Wereley S (eds) Biomems and biomedical nanotechnology, vol IV biomolecu-lar sensing, processing, and analysis. Kluwer, New York... 

Wang W, Soper SA (eds) (2007) BioMEMS technologies and applications. CRC Press, Boca Raton... 

To date, the thermocapacitive flow sensor has only been demonstrated in the semiconductor field for measuring the gas flow rate. Many microfluidic chips and most BioMEMS chips work with a liquid medium. Possible future work includes applications of the thermocapacitive flow sensor in a liquid medium, where electrical insulation would be required. 

While various BioMEMs (Bio-microelectromechanical systems) applications have been demonstrated using conductive polymers, particularly polypyrrole, there has yet been no reported use of conducting polymers solely for implantable biosensor devices. However, recent material advances such as those... 

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