Selective and Sensitive Detection of Hg 2+ and Ag + by a Fluorescent and Colorimetric Probe with Large Stokes Shift

Abstract

Abstract Development of fluorescent sensors with large Stokes shift for selective detection of heavy metals is of great importance. A novel fluorescent probe KL1 with extremely large Stokes shift (212 nm) was synthesized for selective and simultaneous detection of Hg2+ and Ag+ ions. Deep yellow probe KL1 turned colorless or pale yellow after addition of Hg2+ or Ag+. Probe KL1 could be utilized for absorption spectral detection of Hg2+ and Ag+ both in ethanol and aqueous solution. Addition of Hg2+ and Ag+ ions caused significant decrease in the fluorescence intensity of probe KL1 and the selective recognition of Hg2+ and Ag+ was not interfered by common competitive metal ions including Li+, Na+, K+, Cu2+, Fe2+, Zn2+, Co2+, Ni2+, Mn2+, Sr2+, Ca2+, Mg2+, Al3+, Cr3+ and Fe3+. The detection limit for Hg2+ and Ag+ was calculated to be 3.66 μM and 5.76 μM, respectively.