Sensors nanotubes

There are more issues and complexity to be considered if various micro-electromechanical (MEMS)-type devices are included in the macroelectronics tool kit. As described previously, the materials and devices required for TFTs and circuits can provide adequate electromagnetic (visible and RF) sensitivity for many image-type applications. These materials may also provide satisfactory performance in pressure and strain sensors. Nanotube/nanowire-based devices look promising for various chem-bio sensors.85 However, there is little that is known about the ability to integrate printed microfluidic devices (and other such devices with moving parts) into a roll-to-roll-type process. 

A whole new chemistry has been developed around this discovery, and the unusual properties have given rise to suggestions that it could be made into products for a superconducting material, a three-dimensional polymer, new catalysts, new materials with unusual electrical and optical properties and very high mechanical strength, sensors, nanotubes, nanowires, and so on. At this moment, there are, as yet, no products based on the fullerene on the market. 

In this work, simple (single-use) biosensors with a layer double stranded (ds) calf thymus DNA attached to the surface of screen-printed carbon electrode assembly have been prepared. The sensor efficiency was significantly improved using nanostructured films like carbon nanotubes, hydroxyapatite and montmorillonite in the polyvinylalcohol matrix. 

One of the new trends in chemical analysis appeared in the last decade is that the miniaturization. It becomes apparent in the miniaturization of analytical devices, separation procedures, measuring tools, analyzing samples and as a consequent the term micro have appeared. Further development of this trend have led to transfer from the term micro to nano one (nanoparticles, nanofluides, nanoprobes, nanoelectrodes, nanotubes, nanoscale, nanobarcode, nanoelectrospray, nanoreactors, etc). Thereupon a nanoscale films produced by Langmuir-Blodgett (LB) technique are proposed for modifying of chemical sensors. 

Kam, N.W.S. and Dai, H.J. (2005) Carbon nanotubes as intracellular protein transporters generality and biological functionality. Journal of the American Chemical Society, 127 (16), 6021-6026. Heller, D.A. et al. (2005) Single-walled carbon nanotube spectroscopy in live cells towards long-term labels and optical sensors. Advanced Materials, 17 (23), 2793-2799. 

J. Wang and M. Musameh, Carbon nanotube/teflon composite electrochemical sensors and biosensors. Anal. Chem. 75, 2075-2079 (2003). 

Fabrication and application of electrochemical sensors based on carbon nanotubes... 

FABRICATION AND APPLICATION OF ELECTROCHEMICAL SENSORS BASED ON CARBON NANOTUBES... 

One interesting development in the carbon nanotube-based electrochemical sensor is the ability to self-assemble the CNT to other types of nano materials such as gold and silver nanoparticles or to a polymer surface. The enhancement of Raman signals of carbon nanotubes through the adsorption on gold or silver substrate has been also reported [142-146],... 

Even though the number of reports on the electrochemistry based on an individual nanotube is very limited, mainly due to technical difficulty, the development of sensors... 

Q. Zhao, Z. Gan, and Q. Zhuang, Electrochemical sensors based on carbon nanotubes. Electroanalysis 14, 1609-1613 (2002). 

Z. Xu, X. Chen, X. Qu, J. Jia, and S. Dong, Single-wall carbon nanotube-based voltammetric sensor and biosensor. Biosens. Bioelectron. 20, 579—584 (2004). 

L. Wang and Z.B. Yuan, Direct electrochemistry of glucose oxidase at a gold electrode modified with single-wall carbon nanotubes. Sensors 3, 544-554 (2003). 

Several types of palladium-based hydrogen sensors have been reported in the literature. The most notable ones are based on Pd thin-film resistors, FETs, Pd nanowires, Pd nanoparticle networks, Pd nanoclusters, and Pd nanotubes as shown in Table 15.2. 

Kong, J., Chapline, M.G. and Dai, H., Functionalized carbon nanotubes for molecular hydrogen sensors, Advanced Materials, 13(18), 1384, 2001. 

Mor, G.K., Varghese, O.K., Pishko, M.V. and Grimes, C.A., A room-temperature Ti02-nanotube hydrogen sensor able to self-clean photoactively from environmental contamination, Journal of Materials Research, 19(2), 628, 2004. 

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