Spectroscopic and fluorescence properties of silver-dye composite nanoparticles
Abstract
The aim of this work was to investigate the formation of J-aggregates of thiacyanine dye (TC, 5,5'-disulfopropyl-3,3'-dichlorothiacyanine sodium salt) in the presence of 6 nm spherical silver nanoparticles (Ag NPs) using spectrophotometric and fluorescence methods. The formation of J-aggregates was concentration dependent and characterized by the appearance of the new absorption band with the maximum at 481 nm. Spectrophotometric study of J-aggregate formation and time stability suggested that they were formed on the account of monomer form of TC. Moreover, the stability of J-aggregates increased with the lowering AgNPs concentration. The measurements of fluorescence of the NPs—dye assembly clearly indicated that the fluorescence of TC was quenched by Ag NPs on the concentration dependent manner. The spectrophotometric and fluorescence properties of NPs—dye assembly were found to be quantitatively related to the surface coverage of the dye on the Ag NPs.
- Publication:
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Russian Journal of Physical Chemistry A
- Pub Date:
- December 2013
- DOI:
- 10.1134/S0036024413130141
- Bibcode:
- 2013RJPCA..87.2219L
- Keywords:
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- silver nanoparticles;
- cyanine dye;
- J-aggregation;
- fluorescence;
- surface coverage