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PubMed · 16285701

Deposition method for preparing SERS-active gold nanoparticle substrates.

Kiang Wei Kho·Ze Xiang Shen·Hua Chun Zeng·Khee Chee Soo·Malini Olivo
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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).

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ColloidsGentian VioletGoldMetal NanoparticlesMicroscopy, Atomic ForceMolecular StructureSpectrum Analysis, RamanJournal Article

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Kiang Wei Kho, Ze Xiang Shen, Hua Chun Zeng, Khee Chee Soo, Malini Olivo. 2005-11-15. Deposition method for preparing SERS-active gold nanoparticle substrates.. https://doi.org/10.1021/ac050437v

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