A new turn-on fluorescent sensor based on NBD for highly selective detection of Hg2+ in aqueous media and imaging in live cells

Abstract

A new and simple fluorescent probe bearing 7-nitrobenz-2-oxa-1,3-diazole and N,N-bis(thiophen-2-ylmethyl)ethane-1,2-diamine was developed as a fluorescent chemosensor with high selectivity and sensitivity toward Hg²⁺ over other cations tested. The signaling is due to the coordination of S and N atoms of N,N-bis(thiophen-2-ylmethyl)ethane-1,2-diamine to Hg²⁺. Upon addition of 30 equivalents of Hg²⁺, a 45-fold increase in fluorescence emission intensity was observed. Moreover, the probe is further successfully used to image Hg²⁺ in MCF-7 cells.