Diagnostic Applications. Aggregation-Enhanced Fluorescence

A variety of luminescent nanoparticles have been specifically devised for con-focal and multiphoton microscopy. These include nanomaterials, such as silica-based nanoparticles doped with two-photon-absorbing fluorophores, able to exhibit aggregation-enhanced fluorescence, gold nanoparticles, semiconductor nanocrystals (quantum dots/rods), and nanophosphors, viz., ceramic nanoparticles containing luminescent lanthanide ions. 

In the solid state both the shape and the efficiency of fluorescence are affected, due both to the fact that large motions are inhibited and to specific interaction between some moieties of the molecules. In ir—conjugated systems the main 

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