Novel Bis-pyrazoline Fluorescent Probe for Cu²⁺ and Fe³⁺ Detection and Application in Cell Imaging

A fluorescent probe Y((1,1'-([1,1'-biphenyl]-4,4'-diylbis(3-(2-hydroxyphenyl)-4,5-dihydro-1H-pyrazole-5,1-diyl)) bis(ethan-1-one))) was designed and synthesized, which could be used to Cu²⁺ and Fe³⁺ sensors. Through the study of optical properties, the probe Y shows good selectivity and sensitivity to Cu²⁺ and Fe³⁺ in aqueous tetrahydrofuran solution [10.0 mM HEPES, pH 7.4, THF-H₂O = 9:1(v/v)] with has excellent anti-interference performance, and its detection limits were 0.931 uΜ for Cu²⁺ and 0.401uΜ for Fe³⁺. The coordination mechanism of probe Y with Cu²⁺ and Fe³⁺ was speculated and verified at DFT level and HRNM. By Hela cytotoxicity and imaging tests, probe Y not only has good biocompatibility, but also can be used for sensing Cu²⁺ in cells.