A novel dual-excitation and dual-emission fluorescent probe CDs–COO–F for hydrazine detection in aqueous solutions and living cells

Abstract In this work, a novel dual-excitation and dual-emission fluorescent probe, CDs–COO–Fluorescein (CDs–COO–F), for the specific detection of hydrazine (N2H4) was designed and synthesized through esterification reaction of carbon dots (CDs) and fluorescein (F). The prepared CDs were characterized by TEM, XPS, XRD and FT-IR and the optical properties of CDs and CDs–COO–F were described by UV–vis and fluorescence spectra. On the other hand, the affecting factors including hydrazine (N2H4) concentration and interfering substances on the hydrazine (N2H4) detection were researched. The high sensitivity and high selectivity of CDs–COO–F in detection hydrazine (N2H4) could be confirmed. Two good linear responses of fluorescence emission intensities of CDs–COO–F at 462 nm and 515 nm as functions of hydrazine (N2H4) concentration were obtained, respectively. The limits of detection hydrazine (N2H4) were 0.504 μM and 0.269 μM under 370 nm and 480 nm excitation wavelength lights, respectively. The detecting mechanism of hydrazine (N2H4) by CDs–COO–F was deduced from the experimental results. Cell imaging and cytotoxicity experiments of CDs–COO–F were measured. The experiment results show that the fluorescent probe CDs–COO–F can be applied to detect hydrazine (N2H4) in aqueous solution and living cells.