Sensing applications array sensors

Applications of titania nanotube arrays have been focused up to now on (i) photoelectrochemical and water photolysis properties, (ii) dye-sensitized solar cells, (iii) photocatalysis, (iv) hydrogen sensing, self-cleaning sensors, and biosensors, (v) materials for photo- and/or electro-chromic effects, and (vi) materials for fabrication of Li-batteries and advanced membranes and/or electrodes for fuel cells. A large part of recent developments in these areas have been discussed in recent reviews.We focus here on the use of these materials as catalysts, even though results are still limited, apart from the use as photocatalysts for which more results are available. 

Use of computational methods in designing, selecting, and ultimately in optimizing chemical sensing materials and sensor sets for arrays is a growing field, which will assist in development of sensing devices for various applications. 

In summary, carbon materials have a unique structure and unique physical properties. The optimization of these materials for sensing applications depends on how to organize them into the proper configurations. The recent development of one-dimensional nanostmctnres snch as CNTs and CNFs opens up new opportunities that one can electrically wire biomolecules with electronic circuits at molecular levels. Further development in this field is expected to offer highly mnltiplex and miniatnrized sensor arrays with unprecedented sensitivities. 

Shipway AN, Lahav M, Blonder R, WiUner I (1999) Bis-bipyridinium cyclophane receptor- Au neuioparticle superstructures for electrochemical sensing applications. Chem Mater 11 13-15 Shipway AN, Katz E, WiUner 1 (2000) Nanoparticle arrays on surfaces for electronic, opticeil, and sensor applications. Chemphyschem 1 18-52... 

The combinatorial possibility to synthesize a large number of different receptors based on DNA structure has been exploited for the development of luminescent-based sensor arrays [21]. In this case DNA is particularly attractive, because it offers the stability and the versatility as a biopolymer to allow the preparation of a wide range of different structures, which can also be tailored to the particular application. The DNA structure should be functionalized with a fluorescent dye, which acts as the unit signalling the interaction with the analyte. Initially both single and double stranded DNAs have been tested for sensing application, but only the single-stranded DNAs showed different responses to the VOCs tested, which can be related to the DNA sequences exploited. In these preliminary studies DNA oligomers were first stained in solution with two different dyes, both of them... 

Since the advent of the concept of chck chemistry in 2001, it is without question that the click triazole has received most attention, and it has been shown to be an extremely versatile moiety with applications in a wide range of sensing applications, and there is httle doubt that a number of other recent developments will soon be applied in sensing applications [6]. In the vast majority of sensors presented in this chapter, the triazole is integral to the sensing application however, the utility of chck chemistry is seen in its widespread application as a ligation motif in sensors, only some of which are presented herein. It therefore seems likely that in the coming years, practical applications of chck triazole sensors in functional sensor materials for an array of applications will soon be realised. 

So far we have discussed the one-sensor/one-analyte approach. However, arrays of independent electrodes can offer much more analytical information and thus hold a great potential for many practical applications. These include the development of intelligent sensing systems capable of responding to changes in the chemical environment of the array. 

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