Gold Nanoparticles Quench Fluorescence by Phase Induced Radiative Rate Suppression

Abstract

The fluorescence quantum yield of Cy5 molecules attached to gold nanoparticles via ssDNA spacers is measured for Cy5-nanoparticle distances between 2 and 16 nm. Different numbers of ssDNA per nanoparticle allow to fine-tune the distance. The change of the radiative and nonradiative molecular decay rates with distance is determined using time-resolved photoluminescence spectroscopy. Remarkably, the distance dependent quantum efficiency is almost exclusively governed by the radiative rate.

Dissociation coefficients of protein adsorption to nanoparticles as quantitative metrics for description of the protein corona: A comparison of experimental techniques and methodological relevance

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Metal-Enhanced Fluorescence of Chlorophylls in Single Light-Harvesting Complexes

“…[1][2][3][4][5] This versatility results from a dramatic influence that plasmons impose on the absorption and emission properties of nearby located dipoles, for example, semiconductor nanocrystals and nanowires [6][7][8][9][10][11][12] or dye molecules. [13][14][15][16][17][18] Optical response of an emitter coupled to a plasmonic structure depends upon spatial arrangement as well as spectral characteristics of a studied system. Remarkable progress has been made in on-demand design of metal nanostructures, which is essential for tuning the resonance frequency and thus the coupling strength.…”

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