Polyhedral silver mesocages for single particle surface-enhanced Raman scattering-based biosensor

Surface-enhanced Raman scattering-based signal detection and molecular identification faces the lack of reproducibility and reliability thus hampers its practical applications. Here, we demonstrate a facile particle mediated aggregation protocol to synthesize highly roughened mesosuperstructure - silver polyhedral mesocages. The individual silver octahedral mesocage, owing to highly-roughed surface topography, anisotropic growth as well as intraparticle effect, creates homogenously distributed multiple effective hot spots on the surface of single mesoparticle, hereby exhibits a high reproducibility and an unusual SERS enhancement, i.e., similar to 10(8)-10(9) magnitude. As such, the current protocol opens avenues for the fabrication of structurally reproducible mesosuperstructure-based SERS sensors. (C) 2011 Elsevier Ltd. All rights reserved.