A novel imidazo[1,5-a]pyridine-rhodamine FRET system as an efficient ratiometric fluorescent probe for Hg2+ in living cells

An imidazo[1,5-a]pyridine-rhodamine-based ratiometric fluorescent probe was designed and successfully synthesized. The probe shows a large Stokes shift (204 nm), high sensitivity and high selectivity. The detection limit was calculated to be as low as 0.93 nM. The probe could quickly (5 min) detect Hg2+ over a wide pH range from 4 to 10. Furthermore, it could be used for imaging Hg2+ in living cells. (C) 2017 Elsevier Ltd. All rights reserved.