A dicyanisophorone-based probe for dual sensing Zn²⁺ and Cd²⁺ by near-infrared fluorescence

Zinc ions (Zn²⁺) and cadmium ions (Cd²⁺) are widely present in our production and life, which are closely related to human health and environmental protection. Hence, it is essential to detect their concentrations. Herein, we developed a convenient and reliable small-molecule fluorescent probe based on Schiff base of dicyanisophorone and 2-hydrazinopyridine. This probe can be able to selectively detect Zn²⁺ and Cd²⁺, showing the advantages of near-infrared emission (the maximum emission wavelength: 668 nm), good selectivity, high sensitivity (the detection limits: 0.21 µM and 0.31 µM, respectively) and rapid response (15 s). It has excellent potential for rapid testing and visual tracking of Zn²⁺ and Cd²⁺ in aqueous solution and living cells.