关键词: 甲基苯丙胺检测, 荧光探针, 五氟苯甲酰基, 荧光猝灭

Abstract: Ice is one of the mainstream drugs in this century, effective detection and monitoring of ice is an important aspect of ensuring human health and maintaining social stability. The active ingredient of ice is methamphetamine (MA). Aiming at the structural characteristics of both benzene ring and the secondary amine in the MA molecule, two simple small molecule fluorescent probes, 5F-O-TPA and 5F-O-Py were designed and synthesized. The electrostatic attraction of pentafluorophenyl with phenyl ring, combined with the interaction between electron-withdrawing carbonyl groups and secondary electron-rich amines, two factors synergistically contribute to their strong intermolecular interaction, and hence a much efficient PET process and fluorescence quenching. It was found that the two probe molecules have a great difference in the sensing performance of MA. Because 5F-O-Py film has a large specific surface area and good permeability, it can be in good contact with MA molecules. Therefore, in the saturated MA vapor, the fluorescence quenched by 68% within 300 s, and the detection limit of MA vapor can theoretically reach 3.73 ppm, and still has a 38% quenching response after being reversibly used for 6 times. The sensory film has strong anti-interference ability, even its mimetics that are very similar to the MA structure can be effectively distinguished by 5F-O-Py.

Key words: methamphetamine detection, fluorescent probe, pentafluorobenzoyl, fluorescence quenching