摘要

A fluorescent chemodosimeter (TPAII-2) for Hg2+ was designed with four sulphur atoms in its trigger based on a multisulphite strategy and a control sensor (TPAII-1) was synthesized according to the common design with the deprotection of dithiol. Compared to TPAII-1, TPAII-2 displayed optimizing selectivity towards Hg2+ over Ag+, one of the most interference species with strong sulphophile affinity. Further studies indicated the TPAII-2 still maintained the fast detection rate (<2 min) and high sensitivity (detection limited = 15 nM) in HEPES (contain 1% DMSO as cosolvent). As far as we known, sensors based on the deprotection of dithiol were still seldom reported in such solution because of their poor sensing actions in bulk of the aqueous. At last, TPAII-2 was utilized to monitor the Hg2+ in Hela cells, which evidenced TPAII-2 could maintain the excellent sensing properties in more complex circumstance. More importantly, this recognizing method provided a powerful platform for sensing Hg2+ in complex systems and highlighted the designing strategy combing the advantages from both coordination-based and reaction-based fluorescent sensors.