Single-Molecule Detection of Thionine on Aggregated Gold Nanoparticles by Surface Enhanced Raman Scattering

Journal Article · Mon Jan 01 00:00:00 EST 2007 · Journal of Raman Spectroscopy

DOI:https://doi.org/10.1002/jrs.1691· OSTI ID:931492

Ruan, Chuanmin ^[1]; Wang, Wei ^[1]; Gu, Baohua ^[1]

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1. ORNL

We report observations of single molecule detection of thionine and its dynamic interactions on aggregated gold nanoparticle clusters using surface enhanced Raman scattering (SERS). Spectral intensities were found to be independent of the size of Au nanoparticles studied (from 17 to 80 nm) at thionine concentration below 10-12 M or at single molecule concentration levels. Raman line separations and, in particular, spectral fluctuations and blinking also were observed, suggesting temporal changes in single molecular motion and/or arrangements of thionine on Au nanoparticle surfaces. In contrast, by using dispersed Au nanoparticles, only ensemble SERS spectra could be observed at relatively high concentrations (>10-8 M thionine), and spectral intensities varied with the size of Au nanoparticles.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Laboratory Directed Research and Development (LDRD) Program; Work for Others (WFO)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 931492
• Journal Information: Journal of Raman Spectroscopy, Journal Issue: 38
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC
ORGANIC
PHYSICAL AND ANALYTICAL CHEMISTRY
77 NANOSCIENCE AND NANOTECHNOLOGY
THIONINE
DETECTION
GOLD
RAMAN SPECTROSCOPY
NANOSTRUCTURES
RAMAN SPECTRA
Single-molecule SERS
Thionine
gold nanoparticles
Raman spectroscopy