The Applications Of Supramolecular Interaction And Irreversible Reaction In Fluorescent Chemosensors

The applications of molecular recognition have been developed in many fields such as biological imaging, drug delivery, environment detection and anti-terrorism, among which fluorescent chemosensor plays an important role. Development of fluorescent chemosensors with high selectivity and sensitivity is a significant aspect of contemporary supramolecular chemistry.This dissertation is focused on design and synthesis of fluorescence chemosensors based on supramolecular interactions or irreversible reactions. The fluorescent chemosensors for cations (Cu2+, Al3+, Hg2+and Au3+) and anions (picrate, F-and CN-) are developed. The main contents are as follows:1. Three highly selective chemosensors (L1-L3) for Cu2+based on rhodamine are designed and synthesis. Further studies of structure-activity relationship revealed that the designated acyl hydrazone skeleton moiety is responsible for the selectivity for Cu2+over other cations.2. A series of chemosensors (L4-L8) with a variety of aromatic chromophores for specific recognition of picrate have been realized through the fluorescence "on-off" mechanism. They demonstrated highly selectivity and sensitivity to picrate with remarkable visual changes.3. A chemosensor L9which bears an amino alcohol group was synthesized for the fluorescent recognition of Al3+with high selectivety. The significant enhancement of fluorescence intensity was observed that is attributed to the complex formation between L9and Al3+through the chelation-enhanced fluorescence (CHEF) process.4. A bifunctional probe L10for the ratiometric fluorescent sensing for Hg2+and Au3+based on a1,8-naphthalimide and alkyne conjugate in different aqueous solutions is described.5. The reaction-based relay recognition (L11) of fluoride and cyanide anions was demonstrated with rapid response. Ratiometric determination of F-and CN-by fluorescence and/or absorbance spectra is also achieved.