Deposition method for preparing SERS-active gold nanoparticle substrates.
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).
Kho
Kiang Wei
KW
Division of Medical Sciences, National Cancer Centre, Singapore.
Shen
Ze Xiang
ZX
Zeng
Hua Chun
HC
Soo
Khee Chee
KC
Olivo
Malini
M
D003102:Colloids; D005840:Gentian Violet / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D018625:Microscopy, Atomic Force; D015394:Molecular Structure; D013059:Spectrum Analysis, Raman / Q000379:methods*
D003102:Colloids; D006046:Gold; D005840:Gentian Violet