An ultra-sensitive and highly selective fluorescent probe for nickel ions and its environmental and biological applications

Nickel, as a transition metal, is widely used in industrial production and distributed in human body as an essential micronutrient. But the excessive presence of nickel can also cause pollution to the environment and produce harm to human body. Hence, the sensitive detection of metal nickel has attracted widespread attention. Compared with other heavy metal ions, such as mercury ions, lead ions, chromium ions, the reported fluorescence probes for nickel ions are relatively less and lack of simple and effective detection methods. In addition, most of the reported fluorescent probes for nickel ions are of coordination type, which leads to some limitations in sensitivity and selectivity. Therefore, we constructed a reactive fluorescent probe FA-Ni to achieve highly selective and ultra-sensitive recognition of nickel ions. The probe FA-Ni can quickly and sensitively recognize nickel ions (DL = 1.87 nM), avoid the interference of other ions, so as to realize the selective detection of nickel ions. Meanwhile, probe FA-Ni can be used for the detection of nickel ions in environmental water samples and soil samples (recovery rates > 90%), indicating that FA-Ni is of great significance in environmental applications. The probe FA-Ni can also be applied to the detection of nickel ions in living cells and achieve in-situ imaging, which is expected to provide an important auxiliary tool for the diagnosis of related diseases and a powerful means to understand the physiological function of nickel ions.