Biosensors nanowires

Attention has been given to the synthesis of bimetallic silver-gold clusters [71] due to their effective catalytic properties, resistance to poisoning, and selectivity [72]. Recently molecular materials with gold and silver nanoclusters and nanowires have been synthesized. These materials are considered to be good candidates for electronic nanodevices and biosensors [73]. 

The specific properties of novel nanomaterials as nanowires offer an excellent prospect for biological recognition surfaces in order to develop a more selective and sensitive biosensor technology [60-62],... 

The use of nanoparticles has extended throughout the field of biosensors in the electrochemical detection of DNA and immunoreactions (Murphy 2006). A wide range of nanoparticles including nanotubes and nanowires, prepared from metals, semiconductor, carbon or polymeric species, have been investigated. The enhanced electrochemistry is due to the ability of the small nanoparticles to reduce the distance between the redox site of a protein and the electrode, since the rate of electron transfer is inversely dependent on the exponential distance between them (Balasubramanian and Burghard 2006). CNT-modified electrodes have been most frequently used for the development of biosensors (Gooding 2005). 

Fig. 1 Schematic of an LSPR biosensor based on periodic nanowires...

As a quantitative measure of the far-held performance, two quantities may be introduced. First of all, sensitivity enhancement factor (SEF), a ratio of resonance angle shift due to target analyte binding on a nanowire-based biosensor to that of a conventional SPR structure using a thin gold him with equal thickness, is defined as... 

Fig. 5 Plasmon momentum ksp (y-axis in unit of tm ) for various combinations of nanowire depths (dNw) and periods (A), x-axis is VF. Thick and thin solid lines represent the characteristics of a nanowire-hased SPR biosensor with and without a HDT SAM as target analytes. For comparison, the dotted line shows sp( sp = 45.13°) of a SPR biosensor at df = 40 nm without nanowires. Reprinted from [18], Copyright (2006), with permission from the Optical Society of America...

Kim D (2006) Effect of resonant localized plasmon coupling on the sensitivity enhancement of nanowire-based surface plasmon resonance biosensors. J Opt Soc Am A 23 2307-2314... 

Byun KM, Kim S J, Kim D (2006) Profile effect on the feasibihty of extinction-based localized surface plasmon resonance biosensors with metallic nanowires. Appl Opt 45 3382-3389... 

Byun KM, Kim SJ, Kim D (2005) Design study of highly sensitive nanowire-enhanced surface plasmon resonance biosensors using rigorous coupled wave analysis. Opt Express 13 3737-3742... 

Byun KM, Yoon SJ, Kim D et al (2007) Experimental study of sensitivity enhancement in surface plasmon resonance biosensors by use of periodic metallic nanowires. Opt Lett 32 1902-1904... 

Although different nanomaterials such as nanoparticles, nanowires and nanotubes are used for the construction of biosensor, this chapter is mainly devoted to the use of AuNPs for the construction of electrochemical biosensor and their analytical performances. Further, in this chapter we restrict ourselves in the electrochemical sensing of glucose, ascorbic acid, uric acid and dopamine derivatives using the AuNPs modified electrodes. 

T.G., and Chen, Y. (2010) Silicon nanowire biosensor for highly sensitive and rapid detection of Dengue virus. Sensors and Actuators E, 146 (1), 138-144. 

Silicon-based nanowires Real-time detecdon and dtradon of andbodies, viras detecdon, chip-based biosensors 48... 

Wanekaya AK, Chen W, Myung NV, Mulchandani A (2006) Nanowire-based electrochemical biosensors. Electroanalysis 18 533-550... 

Numerous proposals of other applications are scattered throughout this book. To name but a few, CyD-based optical sensors, nanowires, and biosensors are presented in Sections 10.3 and 10.6 and in Table 14.3, respectively. In this chapter a few applications in food and drinks, in cosmetics and toiletry, in the textile and wrapping industries, and in agrochemistry are shown, while the applications of rotaxanes (discussed in Chapter 12) in molecular devices are briefly discussed at the end. 

S. Pal, E. C. Alocilja, and F. P. Downes, Nanowire labeled direct-charge transfer biosensor for detecting Bacillus species, Biosens. Bioelectron., 22, 2329-2336 (2007). 

S.B. Tolani, M. Craig, R.K. DeLong, K. Ghosh, and A.K. Wanekaya, Towards biosensors based on conducting polymer nanowires. Anal. Bioanal. Chem., 393, 1225-1231 (2009). 

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