Towards the Fluorescence Resonance Energy Transfer (FRET) Scanning Near-Field Optical Microscopy: Investigation of Nanolocal FRET Processes and FRET Probe Microscope

Author :S. K. Sekatskii, G. T. Shubeita, M. Chergui, G. Dietler, B. N. Mironov, D. A. Lapshin, and V. S. Letokhov
Publication :Journal of Experimental and Theoretical Physics
Volume :90
Number :5
Pages :769-777
Year :2000

The fluorescence resonance energy-transfer (FRET) process is investigated between donor dye
molecules deposited on the sample surface and acceptor dye molecules deposited on the tips of scanning nearfield
and atomic force microscopes. The FRET process was observed only when the tip acquired contact with
the sample and took place in regions of sizes of only a few tens of nanometers with only a few thousands (or
even hundreds) of molecules involved. The dependence of the FRET intensity on the tip-sample acting force is
recorded and interpreted. In relation to the obtained results, the construction of a previously proposed one-atom
FRET SNOM is described.