Sensor Raman-based

Radical ions, 33, 44 Raman spectroelectrochemistry, 45 Randles-Sevcik equation, 31 Rate constant, 12, 18 Rate determining step, 4, 14 Reaction mechanism, 33, 36, 113 Reaction pathway, 4, 33 Reaction rate, 12 Receptor-based sensors, 186 Redox recycling, 135... 

The metallic nanocrystals are remarkable due to their localized surface plasmon resonance (SPR) phenomenon, that is, the excitation of surface plasma by light. It ensures these nanocrystals to be color based sensors (Homola et al., 1999 Kelly et al., 2003). The metallic nanocrystals could also sensitize the Raman signals from their adsorbed organic molecules. This surface enhanced Raman scattering (SERS) effect potentially raises the detection sensitivity to single molecule level (Kneipp et al., 1997 Nie and Emery, 1997). 

Abstract. Surface-eDhanced Raman scattering is a powerful tool for the investigation of biological samples. Following a brief introduction to Raman and surface-enhanced Raman scattering, several examples of biophotonic applications of SERS are discussed. The concept of nanoparticle-based sensors using SERS is introduced and the development of these sensors is discussed. 

S. Farquharson, P. Maksymiuk, K. Ong, and S. D. Christesen, Chemical agent identification hy surface-enhanced Raman spectroscopy, in Vibrational Spectroscopy-Based Sensor Systems, S. D. Christesen and A. J. Sedlacek El, Eds., Society of Photo-Optical Instrumentation Engineers, Bellingham, WA, 2002, Vol. 4577, p. 166. 

We present here a summary of recent work with light-pulse interferometer based inertial sensors. We first outline the general principles of operation of light-pulse interferometers. This atomic interferometer (Borde et al., 1992 Borde et al., 1989) uses two-photon velocity selective Raman transitions (Kasevich et al., 1991), to manipulate atoms while keeping them in long-lived ground states. 

Chemical modification of CNTs is an essential step towards the fabrication of CNT-based electrochemical sensors. Raman spectroscopy provides an effective way to monitor the modification process and to characterize the functionalized CNTs. 

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],... 

The goal of this chapter will be to provide an overview of the use of planar, optically resonant nanophotonic devices for biomolecular detection. Nanophotonics23 24 represents the fusion of nanotechnology with optics and thus it is proposed that sensors based on this technology can combine the advantages of each as discussed above. Although many of the issues are the same, we focus here on optical resonance rather than plasmonic resonance (such as is used in emerging local SPR and surface-enhanced Raman spectroscopy-based biosensors). 

The most often used detection method for the optical sensors are based on absorption, luminescence, reflectance, and Raman scattering measurements. The basic theory and instrumentation of most of these... 

C.E. Talley, L. Jusinski, C.W. Hollars, S.M. Lane and T. Huser, Intracellular pH sensors based on surface-enhanced Raman scattering, Anal. Chem., 76(23) (2004) 7064-7068. 

J. Kappler, N. Birsan, U. Weimar, A. Dieguez, J.L. Alay, A. Romano-Rodriguez, J.R. Morante, and W. Gopel. Correlation between XPS, Raman and TEM measurements and the gas sensitivity of Pt and Pd doped Sn02 based gas sensors Fresenius Journal of Analytical Chemistry 361 (1998), 110-114. 

In principle, optical chemosensors make use of optical techniques to provide analytical information. The most extensively exploited techniques in this regard are optical absorption and photoluminescence. Moreover, sensors based on surface plasmon resonance (SPR) and surface enhanced Raman scattering (SERS) have recently been devised. 

Typical analysis of blood and urine is based upon chemical reactions, one per chemical species (or analyte ) of interest. Low-accuracy, single-analyte tests such as for blood glucose can be performed using at-home kits comprehensive blood tests at hospitals are performed using dedicated analyzers that suck in a sample and pump portions of it to various sensor modules. The purpose of this chapter is to explore the possibility of using Raman spectroscopy to replace conventional present tests in certain circumstances. 

SERS and SERRS, in particular, are well positioned for applications in the area of highly sensitive and specific biological and chemical detection. This is due primarily to emerging advances in nanotechnology and the development of miniature laser sources and light detection techniques. Two recent reports clearly point to the feasibility of developing sensors based on the surface-enhanced Raman effect. 

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