Fluorescent sensing of anions with acridinedione based neutral PET chemosensor

Abstract

Newly synthesised fluorescent chemosensor ADDTU contains the thiourea receptor connected to the acridinedione (ADD) fluorophore via a covalent bond, giving rise to a fluorophore-receptor motif. In this fluorescent chemosensor, the anion recognition takes place at the receptor site which result in the concomitant changes in the photophysical properties of a ADD fluorophore by modulation of photoinduced electron transfer (PET) process. The binding ability of these sensor with the anions F −, Cl −, Br −, I −, HSO 4 −, ClO 4 −, AcO −, H 2PO 4 − and BF 4 − (as their tetrabutylammounium salts) in acetonitrile were investigated using UV–vis, steady state and time-resolved emission techniques. ADDTU system allows for the selective fluorescent sensing of AcO −, H 2PO 4 − and F − over other anions in acetonitrile.