A novel coumarin-based pyrazoline fluorescent probe for detection of Fe3+ and its application in cells

Abstract

A novel coumarin-based pyrazoline fluorescent probe A was synthesized through a four-step reaction. The structure was characterized by 1H NMR(Nuclear magnetic resonance), 13C NMR and HR-ESI-MS(High resolution electrospray ionization mass spectrometry). The optical properties of the fluorescent probe was investigated by UV–vis absorption and fluorescence emission spectra. The results showed that the addition of Fe3+ makes the fluorescence emission spectra of A quenched and displayed a linear fluorescence response to Fe3+ with a detection limit of 1.01 × 10−7 M. It also shows good reversibility upon addition of EDTA(Ethylene diamine tetraacetic acid). The structure of the fluorescent probe was optimized by DFT(Density functional theory) calculations, and the binding mechanism between the fluorescent probe and the recognition ion was explained. Moreover, the probe also has practical application in cell imaging.