Operating principles Fluorescence 6 Chemical activation 4 Chromophores 4 Fluorescence switching 4 Molecular skeleton 4 Nitrogen compounds 4 Optical resolving power 4 Single molecule level 4 Super resolution imaging 4 Time-scales 4 2,6 dichlorophenolindophenol 2 2-nitrobenzyl 2 Absorption and emission spectroscopy 2 Acetonitrile 2 Analytes 2 Analytical applications 2 Analytical science 2 Antibodies 2 Aquatic organisms 2 Biochemical oxygen demand 2 Bioelectric Energy Sources 2 Biological Assay 2 Biomolecules 2 Biopolymers 2 Characteristic absorption 2 Clostridium butyricum 2 Coumarin derivatives 2 Electric power systems 2 Emission bands 2