Design principles of fluorescent molecular sensors for cation recognition

The main classes of fluorescent molecular sensors for cation recognition ar e presented: they differ by the nature of the cation-controlled photoinduce d processes: photoinduced electron transfer, photoinduced charge transfer, excimer formation or disappearance. In each class, distinction is made acco rding to the structure of the complexing moiety: chelators, podands, corona nds (crown ethers), cryptands, calixarenes. The most representative example s are presented in each subclass with special attention given to selectivit y. (C) 2000 Elsevier Science S.A. All rights reserved.