A dual-functional fluorescent sensor based on dihydropyrazole derivative for successive detection of Cu2+ and glyphosate and its applications

A novel "on-off-on" fluorogenic sensor DHPS based on dihydropyrazole-derived acylhydrazone was devised for sequent Cu2+ and glyphosate detection in DMSO/H2O (95:5, v/v, HEPES 20 mM, pH=7.4) solution. DHPS exhibited a linear range of 0.1-9 mu M, a detection limit of 47 nM, and a highly selective and sensitive fluorescence quenching response towards Cu2+. DHPS-Cu2+ complex showed excellent detection capability for glyphosate, a linear range of 0.5-11 mu M, a detection limit of 52 nM, a wide pH range of 4.0 to 9.0, and a good selective and sensitive fluorescence recovery response. Besides, DHPS and DHPS-Cu2+ complex could detect Cu2+ and glyphosate in real water, respectively, and exhibited good stability and practicality, which provided some valuable ideas for the design of corresponding fluorescent probes in the future.