[1] [1] K. E. Sapsford, L. Berti, I. L. Medintz, Materials for fluorescence resonance energy transfer analysis: Beyond traditional donor-acceptor combinations, Angew. Chem. 45, 4562 (2006).

[2] [2] G.-S. Jiao, L. H. Thoresen, K. Burgess, Fluorescent, through-bond energy transfer cassettes for labeling multiple biological molecules in one experiment, J. Amer. Chem. Soc. 125, 14668 (2003).

[3] [3] R. Guliyev, A. Cosk, E. U. Akkaya, Design strategies for ratiometric chemosensors: Modulation of excitation energy transfer at the energy donor site, J. Amer. Chem. Soc. 131, 9007 (2009).

[4] [4] R. M. Franzini, E. T. Kool, Efficient nucleic acid detection by templated reductive quencher release, J. Amer. Chem. Soc. 131, 16021 (2009).

[5] [5] X. Zhang, Y. Xiao, X. Qian, A ratiometric fluorescent probe based on FRET for imaging Hg2+ ions in living cells, Angew. Chem. Int. Ed. 47, 8025 (2008).

[6] [6] H. Yu, Y. Xiao, H. Guo, X. Qian, Convenient and efficient FRET platform featuring a rigid biphenyl spacer between rhodamine and BODIPY: Transformation of `turn-on' sensors into ratiometric ones with dual emission, Chem. Eur. J. 17, 3179 (2011).

[7] [7] H. Yu, M. Fu, Y. Xiao, Switching off FRET by analyte-induced decomposition of squaraine energy acceptor: A concept to transform `turn off' chemodosimeter into ratiometric sensors, Phys. Chem. Chem. Phys. 12, 7386 (2010).