Single-molecule measurements of gold-quenched quantum dots.
We report the study of the quenching of quantum dots (CdSe) by gold nanoparticles at the single-molecule level. Double-stranded DNA is used as a rigid spacer to tune the distance between the two nanoparticles. The width of the fluorescent intensity distribution, monitored at different interparticle distances, reflects both the nanoparticle heterogeneity and the fluorescence intermittency of the quantum dot. The fluorescence distribution emitted by single CdSe nanocrystals can easily be distinguished from the fluorescence of partially quenched CdSe. Our results show that the distance-dependence quenching is compatible with a Förster-type process.
Gueroui
Zoher
Z
Center for Studies in Physics and Biology, The Rockefeller University, 1230 York Avenue, New York, New York 10021, USA. zoherg@rockefeller.edu
Libchaber
Albert
A
D019187:Cadmium Compounds / Q000737:chemistry*; D004247:DNA / Q000737:chemistry*; D005453:Fluorescence; D006046:Gold / Q000737:chemistry*; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013050:Spectrometry, Fluorescence
D019187:Cadmium Compounds; D018036:Selenium Compounds; D006046:Gold; D004247:DNA; C058667:cadmium selenide