Surface-enhanced Raman spectrometry for trace organic analysis

Plasmon Resonances of Nanoshells of Spheroidal Shape

“…These are bulk values for silver obtained by fitting (1) to the data of Johnson and Christy [33]. These values are close to but not identical to the values obtained by Oubre and Nordlander from the same data set [34].…”

“…Our laboratory has been involved in the investigation and application of plasmonics nanosubstrates for SERS detection for over two decades. Since our first report on the practical analytical use of the SERS techniques for the trace analysis of a variety of chemicals including several homocyclic and heterocyclic polyaromatic compounds in 1984 [1], our laboratory has been involved in the development of SERS technologies for applications in chemical sensing, biological analysis and medical diagnostics [2]- [8]. Our substrates involve nanoparticles and seminanoshells consisting of a layer of nanoparticles coated by silver on one side (halfshells).…”

“…In our analysis, we shall not attempt to correct for these effects. Finally, we employ the Drude free-electron model for the frequency-dependence of the dielectric constant, given by (1) where ω p is the plasma frequency of the bulk material, γ is the width of the resonance and ε ∞ is a constant assumed independent of ω as a first approximation. In view of the above assumptions, we expect only qualitative agreement with experimental results.…”

Surface‐enhanced Raman scattering for medical diagnostics and biological imaging

“…In 1984, the general applicability of SERS as an analytical technique for the trace detection of a wide variety of chemicals using solid substrates covered with silver-coated nanospheres was first demonstrated in our laboratory. 4 This SERS technique, based on metallic nanostructures, has been further developed and applied to the detection of environmental pollutants and biomarkers of health effects. 5 -13 The SERS technique has also been used in the investigation of adsorption and reaction processes at electrochemical interfaces.…”

“…However, in SERS, the Raman scattering efficiency can be enhanced by factors of up to 10 13 when the probed molecules are adsorbed on or near special metallic nanostructures. Since our first report on the practical analytical use of the SERS techniques for trace analysis, 4 our laboratory has been involved in the development of SERS technologies for applications in chemical sensing 5 -13 and medical diagnostics. 29 -34 In addition, SERS studies on living cells using gold nanoparticles have been reported.…”