A simple Schiff base fluorescence probe for highly sensitive and selective detection of Hg2+ and Cu2+

A new Schiff base fluorescent probe, 2-(4-(diphenylamine)benzylidene) thiosemicarbazide (DPBT), was synthesized and its sensing behavior to metal ions were studied by UV-vis and fluorescence spectra. The results show that DPBT can detect Hg2+ sensitively and selectively in weakly acidic and neutral conditions, they form a complex with 2:1. The linear range was 0.095-1.14 mu M and the detection limit was 0.15 nM. In weakly alkaline conditions, DPBT can interaction with Hg2+ and Cu2+ at the same time. We use masking reagent, NaBH4, to reduce Hg2+ to Hg degrees, the detection of Cu2+ were achieved. They formed 1:1 complex with the binding constant of 4 x 10(4) M-1, a good linear relationship in 0.45-3.6 mu M and the detection limit of 0.17 mu M. The proposed method was used to determine Hg2+ and Cu2+ in tap water and waste water samples. (c) 2016 Elsevier B.V. All rights reserved.