An unusual OFF-ON fluorescence sensor for detecting mercury ions in aqueous media and living cells.

A novel azo derivative sensor (BDAA) based on alkynes was designed and utilized to direct detection of Hg(2+) in aqueous solution and living cells. The new strategy achieved off to on switchable fluorescence. permits the highly selective and sensitive detection of Hg(2+). This sensor can be used for imaging of Hg(2+) in living cells.