Flavonols and 3-hydroxychromones: new applications for a class of environment-sensitive fluorescent molecules
Résumé
Flavonols are naturally-occuring molecules that exhibit interesting fluorescence properties. Thanks to an excited-state intramolecular proton transfer, to specific interactions with their molecular environment and to ground-state proton transfer reactions, very often a dual or even triple fluorescence (with well-separated emission bands and strong Stokes shifts) is observed. This phenomenon has been largely exploited in the past, and has led to the development of several synthetic 3-hydroxychromones, structurally very similar to flavonols, used as fluorescent probes.
In this feature article, we highlight some recent and innovative developments in the applications of flavonols and 3-hydroxychromones, notably in the fields of fluorescence chemosensors, environment-sensitive fluorophors, bioimaging, and bacteria identification. Such results show the extraordinary versatility of the 3-hydroxychromone structure for the development of various strategies of exploiting the fluorescence of 3-hydroxychromones and flavonols in a large number of analytical and research fields.