A fluorescent probe for the dual-channel detection of Hg2+/Ag+ and its Hg2+-based complex for detection of mercapto biomolecules with a tunable measuring range

A novel squaraine dye (SQ-1) was developed and its chemosensor behavior toward various metal ions was explored. SQ-1 exhibited selectivity and sensitivity to Hg2+ and Ag+ compared to other metal ions, and it can detect Hg2+ and Ag+ by use of an EDTA reversible experiment. More importantly, the SQ-1-Hg2+ complex can also serve as a colorimetric and fluorescent turn-on sensor for thiol-containing biomolecules, and a dynamic measuring range could be obtained by adjusting the concentration of Hg2+.