Deposition method for preparing SERS-active gold nanoparticle substrates

Anal Chem. 2005 Nov 15;77(22):7462-71. doi: 10.1021/ac050437v.

Abstract

Surface-enhanced Raman scattering or SERS, discovered some 20 years ago, has recently become a promising tool for routine biofluid assays in a clinical setting. Many attempts have been made to produce cheap and reproducible SERS-active substrates. In this study, we report on the fabrication of SERS-active substrates through the convective assembly of gold (Au) particles on electrostatically charged glass slides. We show that, by a proper control of the initial particle concentration in an evaporating Au suspension droplet, it is possible to obtain a closely packed colloidal film capable of generating SERS activity. Finally, AFM and SERS measurements of the resulting films reveal comparability in performance with previous silane-immobilized Au colloidal films. The minimum electromagnetic enhancement factor of our films is estimated to be about 2 x 10(4).

MeSH terms

  • Colloids
  • Gentian Violet / chemistry
  • Gold / chemistry*
  • Metal Nanoparticles / chemistry*
  • Metal Nanoparticles / ultrastructure
  • Microscopy, Atomic Force
  • Molecular Structure
  • Spectrum Analysis, Raman / methods*

Substances

  • Colloids
  • Gold
  • Gentian Violet