
141Biosensing Based on Surface-Enhanced Raman Spectroscopy
NPs of metals [142,143], or metallic compounds [144]. The SERS enhancement is mostly due
to two kinds of effects: an EM effect associated with large local elds due to resonances
occurring in the nanostructure on the metal surface, and a chemical effect involving a
scattering process associated with the chemical interaction between the molecule and the
metal surface.
For the SERS substrates based on SiNW, they report two kinds of silicon nanow-
ires used for the basic materials. One kind of SiNWs was prepared by oxide-assisted
growth via the thermal evaporation of the SiO powder and the ...