Dual-mode sensing platform based on colloidal gold functionalized porous silicon

We report a dual-mode sensing platform based on a single layer porous silicon (PSi) film impregnated with colloidal gold nanoparticles. This gold-coated PSi film supports both quantification of molecular binding via reflectance measurements and molecular identification via surface enhanced Raman scattering (SERS). A detection sensitivity of approximately 400 nm/RIU was demonstrated through binding of benzenethiol molecules. Identification of the unique SERS peaks was possible with uniform signal intensity across the sample and a detection limit below 1 mu M. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3503608]