The local field dependent effect of the critical distance of energy transfer between nanoparticles

•The fluorescence resonance energy transfer between fluorophore pairs was investigated.•The very large micrometer critical transfer distance d0 was obtained.•The model "wave emitter station and antenna" is given to explain the obtained results.•The theoretical compute shows the ability of d0 to reach to micrometer scale.

The fluorescence resonance energy transfer between various types of fluorophore pairs was investigated. Dye molecules, quantum dots, fluorescent nanoparticles (dye molecules encapsulated in polymer matrices) were used as donor D. Dye molecules and gold nanoparticles were used as acceptor A. We found that the experimental Förster critical transfer distance R0 is 1–10 nm when both D and A are dye molecules, and becomes larger than 10 nm when the donor is fluorescent nanoparticles. When the acceptors A are gold nanoparticles, the case is considered as localized plasmon coupled nanosurface energy transfer (NSET), the experimental critical distance d0 increases up to few ten nanometers when D are dye molecules or quantum dots. For the first time, un-expected giant resonance energy transfer (G-RET) phenomenon is observed in our experiments with very large critical transfer distance d0, which increases from few ten nanometers to micrometers when the donors are fluorescent and the acceptors are gold nanoparticles. A model “nanowave emitter station and antenna” is given to explain the local field dependence of the critical distance of energy transfer between those nanoparticles. Moreover, a simple theoretical model with size–number contribution (for fluorescent nanoparticles) and surface plasmon coupled enhancement effect (for gold nanoparticles) is proposed to explain these obtained experimental results.