A new acylhydrazine N'-(1,3 dimethylbutylene)-3-hydroxy-naphthohydrazide based fluorescent sensor for the detection of Ni²⁺

In this paper, a novel hydrazide compound (N'-(1,3 dimethylbutylene)-3-hydroxy-naphthohydrazide) (BMH) was synthesized by a simple three-stage reaction and its chemical structure was confirmed by ¹H NMR, ¹³C NMR and FTIR characterization. This compound was used as fluorescent sensor for the detection of Ni²⁺ based on photoluminescence quenching. The fluorescence quenching of BMH upon the addition of Ni²⁺ is due to the formation of coordination complex which was verified by bind model and density functional theory studies. The Ni²⁺ concentration dependent fluorescence quenching efficiency of BMH was examined and the detection conditions were optimized. There is a good linear relationship between the emission intensity quenching (ΔF = F₀–F) and the Ni²⁺ concentration (c) between 80 nM and 2 μM and the detection limit is 60 nM. The simple preparation of the compound BMH and the high sensitivity of the fluorescent sensor hold great promise for the determination of Ni²⁺ in environment.