Microsensor arrays

Wygladacz K, Radu A, Xu C, Qin Y, Bakker E (2005) Fiber-optic microsensor array based on fluorescent bulk optode microspheres for the trace analysis of silver ions. Anal Chem 77 4706 1712... 

Wygladacz K, Bakker E (2007) Fluorescent microsphere fiber optic microsensor array for direct iodide detection at low picomolar concentrations. Analyst 132 268-272... 

A multi-microsensor array of potentiometric MIP chemosensors has been devised for determination of a serotonin neurotransmitter [180]. In the toluene porogenic solvent solution, the MAA functional monomer and the EGDMA cross-linker were polymerized in the presence of the serotonin hydrochloride template (Table 6). Subsequently, the resulting MIPs were immobilized on a plasma polymer layer by swelling and polymerization. Plasma polymerization was performed using styrene or ethylbenzene as the monomer. The chemosensor fabricated that way was appreciably responsive to serotonin while selectivity to serotonin analogues, like acetaminophen... 

Ping et al. have fabricated an integrated microsensor array on a silicon wafer for pH imaging [89]. Six different pH-sensitive colorimetric dyes (methyl violet 6B, phenolic red, alizarin complexone, 5-carboxy-fluorescein, alizarin red and methylthymol blue) were used to cover the whole pH range. The dyes were adsorbed on microbeads and placed in etched microwells on the silicon wafer. The indicator array was also used as a cation sensor chip (see Sect. 2.4). 

Future directions in biosensors will require the miniaturization of individual sensors for in-vivo use, and for use in microsensor arrays (7). Ideally, these biosensors should be capable of direct, rather than differential measurement, and should have reasonable lifetimes. 

Grate, J.W. (2000). Acoustic wave microsensor arrays for vapor sensing. Chem. Rev. 100 2627-48. 

Several challenges remain for the ultimate practical use of these sensors. The response time of the solid state sensors are short (seconds) for initial sensing, but recovery times range from minutes to hours at room temperature. The stability of the sensor to drift associated with accumulation of fixed charge at interfaces, as well as the high sensitivity to ubiquitous urban pollutants ozone and N02 are problematic. All MPc OTFTs show some response to moisture, and conductivity is also temperature sensitive so that humidity and temperature compensation are essential. On a basic research level, the detailed characterization of charge trapping states, electronic structure, and the interactions with analytes is not yet fully understood on a quantitative theoretical basis. The time response of sensor initiation and recovery is also not understood in a detailed manner. In spite of these limitations, the intrinsic chemical stability of MPc compounds and their compatibility with microsensor array fabrication make these candidate OTFTs for further research and development. 

Optical microsensor arrays for explosives detection David Walt and Tamar Sternfeld... 

Gardner J. W., Microsensor array devices, in Microsensors Principles and Applications (Chichester Wiley, 1994), 279. 

ZnO devices can also be classified into three types thick-film, thin-film, and microsensor (array). In addition, the additives to the films serve to make the sensors sensitive, selective, stable, etc. 

Microsensor arrays can be obtained by applying a combination of the integrated circuit process and microelectromechanical (MEMS) techniques. Using this array, we can enhance the selectivity and reliability of the system, employing statistical techniques. 

Figure 14.8 shows the arrangement of the microsensor array. The sensing membrane area was undercut so that the part can be heated with a comparatively low level of power. 

Microsensor array arrangements (a) sensing electrode heater (front), (b) etching figure on reverse (back heater), (c) device for sensing thick-film formation, (d) mounted on PCB. 

Koickal, T. I, Hamilton, A., Tan, S. L., Covington, I, Gardner, J. W. and Pearce, T. (2005) Smart interface circuit to ameliorate loss of measurement range in chemical microsensor arrays. Proceedings of the IEEE Instrumentation and Measurement Technology Conference. Ottawa, Ont., Canada. 

E. Lindner, V. V. Cosofret, S. Ufer, R. P. Buck, R. P. Kusy, R. B. Ash, H. T. Nagle, Flexible (kapton-based) microsensor arrays of high-stability for cardiovascular applications, Journal of the Chemical Society - Faraday Transactions 1993, 89, 361. 

Guiseppi-Elie, A.. Wilson, A. M., Tour, J. M., Brockmann, T. W., Zhang, R, and Allara, D. L., Specific immobilization of electropolymerized polypyrrole thin films onto interdigitated microsensor array electrodes, Langmuir, 11, 1768 (1995). 

Grate JW (2000) Acoustic wave microsensor arrays for vapor sensing. Chem Rev 100 2627-2647 Grate JW, Patrash SJ, Abraham MH, Du CM (1996) Selective vapor sorption by polymers and cavitands on acoustic wave sensors is this molecular recognition Aneil Chem 68 913-917 Gutsche CD (1989) Calixarene. The Royal Society of Chemistry, Cambridge... 

Ward BJ, WUcher K, Hunter G (2010) Gas microsensor array development targeting enhanced engine emissions testing. In AIAA Infotech Aerospace 2010, AIAA, Reston, 20-22 Apr 2010, AIAA 2010-3327... 

In addition to forming continuous organometallic multilayer thin films, we explored the LbL deposition of polyferrocenylsilane polyions onto, for instance, hydrophilically/hydrophobically modified substrates with the aim of building two-dimensionally patterned organometallic multilayers. In general, surfaces modified with microscopically patterned conducting, luminescent, or redox-active polymer films have potential use in microelectronic and optoelectronic devices and microsensor arrays. Area-selective deposition of polyferrocenylsilane polyions can be an attractive method to obtain two-dimensionally patterned redox active films, which may be used as electrochemically modulated diffraction gratings. ... 

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