Single surface-enhanced, SERS

Kneipp K, Wang Y, Kneipp FI, Perelman L T, Itzkan I, Dasari R R and Feld M S 1997 Single molecule detection using surface-enhanced Raman scattering (SERS) Phys. Rev. Lett. 78 1667-70... 

Since most biomolecules normally exhibit medium or low Raman cross sections, an enhancement of the signal intensity for the ability to characterize even low concentrations would be preferable. Besides the application of resonance Raman spectroscopy, surface-enhanced Raman spectroscopy (SERS) is a promising alternative. In doing so the vicinity of molecules to rough noble metal surfaces leads to Raman enhancement factors of 106-108 and even up to 1014 leading to a single molecule detection limit [9]. 

Kneipp, K., Kneipp, H., Itzkan, I., Dasari, R. R. Feld, M. S. Single molecule detection using near infrared surface-enhanced Raman scattering. Springer Ser. Chem. Phys. 67, 144-160 (2001). 

Surface enhanced Raman spectroscopy (SERS) experiments on silver and gold nanoclusters have demonstrated large enhancement levels and field confinement of 5 nm or less for various samples such as single-walled carbon nanotubes.1 However, the locations of these conditions cannot be controlled but are instead determined by the specific nanostructures used. That is, the target molecules have... 

The extremely small cross sections for conventional Raman scattering, typically 10 111 to 10-25 cm2/molecule has in the past precluded the use of this technique for single-molecule detection and identification. Until recently, optical trace detection with single molecule sensitivity has been achieved mainly using laser-induced fluorescence [14], The fluorescence method provides ultrahigh sensitivity, but the amount of molecular information, particularly at room temperature, is very limited. Therefore, about 50 years after the discovery of the Raman effect, the novel phenomenon of dramatic Raman signal enhancement from molecules assembled on metallic nanostructures, known as surface-enhanced Raman spectroscopy or SERS, has led to ultrasensitive single-molecule detection. 

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). 

SERS. See Surface enhanced Raman scattering Si(lOO), 135 Si(lll), 135 Si3N4,415 Single... 

Le Ru, E. C., Meyer, M., and Etchegoin, P. G. (2006). Proof of Single-Molecule Sensitivity in Surface Enhanced Raman Scattering (SERS) by Means of a Two-Analyte Technique. J. Phys. Chem. B 110 1944-1948. 

Sun B, Jiang X, Dai S, Du Z (2009) Single-crystal silver nanowires preparation and Surface-enhanced Raman Scattering (SERS) property. Mater Lett 63 2570-2573... 

Le Ru EC, Meyer M, Etchegoin PG (2006) Proof of single-mokeule sensitivity in surface enhanced Raman scattering (SERS) by means of a two-analyte technique. J Phys Chem B 110(4) 1944-1948... 

Blackie E, Le Ru EC, Meyer M, Timmer M, Burkett B, Northcote P, Etchegoin PG (2008) Bi-analyte SERS with isotopically edited dyes. Phys Chem Chem Phys 10(28) 4147 153 Dieringer JA, Lettan RB, Scheidt KA, Van Duyne RP (2007) A frequency domain existence proof of single-molecule surface-enhanced Raman spectroscopy. J Am Chem Soc 129(51) 16249-16256... 

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