Spectroscopic tags using dye-embedded nanoparticles and surface-enhanced Raman scattering.
Surface-enhanced Raman scattering is capable of providing rich vibrational information at the level of single molecules and single nanoparticles, but the practical applications of this enormous enhancement effect are still a challenge. Here we report a new class of dye-embedded core-shell nanoparticles that are highly efficient for surface Raman enhancement and could be used as spectroscopic tags for multiplexed detection and spectroscopy. The core-shell particles contain a metallic core for optical enhancement, a reporter molecule for spectroscopic signature, and an encapsulating silica shell for protection and conjugation. A surprising finding is that organic molecules with an isothiocyanate (-N=C=S) group or multiple sulfur atoms are compatible with silica encapsulation. In comparison with fluorescent dyes and quantum dots, enhanced Raman probes contain a built-in mechanism for signal amplification and provide rich spectroscopic information under ambient experimental conditions.
Doering
William E
WE
Departments of Biomedical Engineering and Chemistry, Emory University and Georgia Institute of Technology, 1639 Pierce Drive, Suite 2001, Atlanta, Georgia 30322, USA.
Nie
Shuming
S
D002232:Carbocyanines / Q000737:chemistry; D004396:Coloring Agents / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D017879:Isothiocyanates / Q000737:chemistry; D008854:Microscopy, Electron; D015394:Molecular Structure; D036103:Nanotechnology; D017640:Silicates / Q000737:chemistry; D013059:Spectrum Analysis, Raman / Q000295:instrumentation* / Q000379:methods*; D014732:Vibration
D002232:Carbocyanines; D004396:Coloring Agents; D017879:Isothiocyanates; D017640:Silicates; D006046:Gold