Development of the Surface Enhanced Raman Scattering based sensors

Summary

Surface Enhanced Raman Scattering (SERS) manifests itself by 105-1012 increase of the Raman signal compared to what one expects from the theoretical calculations. Such increase is observed only when the analyte is in the contact with the SERS-active substrate. Surface preparation requires introduction of the nano-size (no larger than 20nm in diameter) particles. The enhancement of the Raman signal is remarkable. Several recent papers claim detection of the SERS for single molecules [Kneipp 1997], [Nie 1997], [Xu 1999]. Strong SERS signal allows one to suggest a detection system based on a miniature Raman spectrometer combined with the specifically “tuned” SERS-active substrate. By tuning we mean a substrate with the nanoparticles of particular size and spacing resulting in the enhanced Raman signal of a specific analyte.

References:
[Kneipp 1997] K. Kneipp, Y. Wang, H. Kneipp, L. Perelman, I.Itzkan, R.R.Dasari, M.S.Feld, Phys. Rev. Letters 78, 1667 (1997)
[Nie 1997] S. Nie, S.R. Emory, Science 275, 1102 (1997)
[Xu 1999] H. Xu, E.J. Bjerneld, M. Käll, L. Börjesson, Phys. Rev. Lett. 83, 4357 (1999)