Reaction-based fluorescence probes for "turn on" sensing fluoride ions.

Introducing a weak covalent bond into an originally highly fluorescent molecule to create a non-fluorescent probe is able to provide a new way to detect some nucleophilic targets with enhanced sensitivity. Herein, this is the first time that a tetraphenylethene (TPE)-based probe (TPEONO) bearing a -nitrobenzenesulfonyl moiety for the sensing of F ions in aqueous solution a cleavage reaction of the sulfonyl ester bond to induce aggregation-induced emission (AIE) has been reported.