A Bis(Salamo)-Based Fluorogenic Sensor for Highly Selective and Sequential Recognition of Cu2+ and B4O72- Ions in Semi-Aqueous Medium.

A new type of multifunctional bis(salamo)-based fluorogenic sensor H2BS was designed and synthesized. Under the action of VDMF: VH2O = 9: 1, the fluorogenic sensor can identify Cu2+ and B4O72-, in which N and O atoms can serve as binding sites for Cu2+ and B4O72-, the stoichiometry of the binding of the fluorogenic sensor H2BS and Cu2+ has been confirmed by titration experiment, working curve, ESI-MS analysis and DFT calculation. The pH response experiment also confirmed that the fluorogenic sensor can recognize Cu2+ and B4O72- in the pH range applicable to the physiological environment. The minimum detection limit of H2BS for Cu2+ and B4O72- recognition reaches 1.12 × 10-7 and 5.56 × 10-8 M, and the fluorogenic sensor H2BS has been successfully applied to Cu2+ detection in actual water samples, and the test strip for detecting Cu2+ and B4O72- was obtained. Meanwhile, the success of the test strip experiment made the fluorogenic sensor H2BS to recognize Cu2+ and B4O72- widely used in daily life. A new type of salamo-based multifunctional fluorogenic sensor H2BS was designed and synthesized to identify Cu2+ and B4O72- in aqueous solvent systems. Added Cu2+ to H2BS can cause fluorescence quenching. Further experiments showed that H2BS and Cu2+ form a stable 1:2 complex, while B4O72- can also cause fluorescence quenching of H2BS, which is the occurrence of the PET effect. Meanwhile, H2BS can be used for quantitative detection in the environment and rapid identification in life.