Myricetin-based fluorescence probes with AIE and ESIPT properties for detection of hydrazine in the environment and fingerprinting

Hydrazine (N2H4) is a highly toxic and versatile chemical raw material, which poses a serious threat to the environment and human health when used in large quantities. However, the traditional methods for the detection of N2H4 have the disadvantages of time-consuming, complicated operation and expensive instruments. In contrast, fluorescence probes have many advantages, such as simple operation, high sensitivity, good selectivity, and fast response time. Therefore, there is an urgent need for a fluorescence probe that can rapidly and accurately detect the presence of N2H4 and monitor the changes in its concentration. For this purpose, we designed and synthesized a series of myricetin fluorescence probes 3-(substituent group)-5,7-dimethoxy-4-oxo-2-(3,4,5-trimethoxy. phenyl)-4H-chromen-4-one (Myr-R) for N2H4 detection. In the presence of N2H4, the probe 5,7-dimethoxy-3-(2,3,4,5,6-pentafluorobenzoate)-2-(3,4,5-trimethoxyphen-yl). -4H-chr-omen-4-one (Myr-3) shows significant fluorescence changes, double emission properties and a large Stokes shift (183 nm), and exhibits high selectivity and sensitivity to N2H4 (The detection limit is 93 nM). Importantly, the qualitative and quantitative analysis of N2H4 in water, soil, and air can be accomplished using fluorescence, smartphone, and UV lamps coupled with Myr-3. In addition, Myr-3 can be used for monitoring and imaging intracellular N2H4. Meanwhile, the fluorophore 3-hydroxy-5,7-dimethoxy-2-(3,4,5-trimethoxyphenyl)-4H-benzopyran-4-one (Myr-Me) was applied to fingerprinting of different substrate materials due to the fact that it exhibits strong yellow fluorescence emission in the solid state and shows excellent contrast and high resolution. The probe Myr-3 is not only able to rapidly detect N2H4 in complex environments, but also can be used for imaging intracellular N2H4. In addition, the fluorophore Myr-Me can be used as an effective imaging agent for visual fingerprinting. These properties enable the probe Myr-3 and the fluorophore Myr-Me for a wide range of potential applications in related fields.