Silver-coated silica beads applicable as core materials of dual-tagging sensors operating via SERS and MEF.
We have developed dual-tagging sensors, operating via both surface-enhanced Raman scattering (SERS) and metal-enhanced fluorescence (MEF), composed of silver-coated silica beads onto which were deposited SERS markers and dye-grafted polyelectrolytes, for multiplex immunoassays. Initially, a very simple electroless-plating method was applied to prepare Ag-coated silica beads. The Raman markers were then assembled onto the Ag-coated silica beads, after which they were brought to stabilization by the layer-by-layer deposition of anionic and cationic polyelectrolytes including a dye-grafted polyelectrolyte. In the final stage, the dual-tagging sensors were assembled onto them with specific antibodies (antihuman-IgG or antirabbit-IgG) to detect target antigens (human-IgG or rabbit-IgG). The MEF signal was used as an immediate indicator of molecular recognition, while the SERS signals were subsequently used as the signature of specific molecular interactions. For this reason, these materials should find wide application, especially in the areas of biological sensing and recognition that rely heavily on optical and spectroscopic properties.
Kim
Kwan
K
Department of Chemistry, Seoul National University, Seoul 151-742, Korea. kwankim@snu.ac.kr
Lee
Yoon Mi
YM
Lee
Hyang Bong
HB
Shin
Kuan Soo
KS
D000818:Animals; D000888:Antibodies, Anti-Idiotypic / Q000378:metabolism; D005453:Fluorescence; D006801:Humans; D007118:Immunoassay / Q000379:methods; D007074:Immunoglobulin G / Q000378:metabolism; D008863:Microspheres; D011817:Rabbits; D012822:Silicon Dioxide / Q000737:chemistry*; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013194:Staining and Labeling / Q000379:methods*
D000888:Antibodies, Anti-Idiotypic; D007074:Immunoglobulin G; D012834:Silver; D012822:Silicon Dioxide