A new thiosemicarbazone fluorescent probe based on 9,9′-bianthracene for Hg2+ and Ag+

Abstract A new 9,9′-bianthracene-based thiosemicarbazone ( D1 ) has been successfully synthesized and utilized for chemosensors. The properties of D1 were systematically investigated by UV–Vis, fluorescence titration and theoretical calculations. As a result, D1 exhibits a characteristic fluorescence quenching phenomenon in the presence of Hg 2+ or Ag + compared to other metal cations (Na + , K + , Mg 2+ , Ba 2+ , Al 3+ , Zn 2+ , Fe 2+ , Pb 2+ , Cu 2+ , Co 2+ , Cd 2+ , Ni 2+ and Mn 2+ ). The detection limits of Hg 2+ and Ag + reach 6.62 × 10 −7  M and 1.99 × 10 −5  M, respectively. This is mainly attributed to the Hg 2+ (or Ag + ) forms a stable five-membered ring with the N atom in Schiff base C N and the S atom in thiourea. The results suggest that the probe D1 is a promising candidate for chemosensors in aqueous media due to its highly selectivity for Hg 2+ and Ag + .