Transparent Raman-enhancing substrates for microbiological monitoring and insitu pollutant detection

Abstract

Opaque Raman-enhancing substrates made of Ag nanoparticles on incompletely oxidized aluminum templates have been rendered transparent by an ion-drift process to complete the oxidation. The result shows that the transparent substrates exhibit high/uniform surface-enhanced Raman scattering (SERS) capability and good optical transmissivity, allowing for concurrent SERS characterization and high contrast transmission-mode optical imaging of S.aureus bacteria. We also demonstrate that the transparent substrates can used in conjunction with optical fibers as SERS sensors for insitu detection of malachite green down to 10- 9M. © 2011 IOP Publishing Ltd.