An Ultra-Sensitive Naphthalimide-Derived Fluorescent Probe for the Detection of Cu2+ in Water Samples and Living Cells

摘要

In this work, a highly sensitive and selective fluorescent probe L based on naphthalimide derivative is developed for detection of Cu2+ ion in water samples and living cells. The probe displays excellent performance with great selectivity for Cu2+ ion detection in CH3CN/phosphate buffered saline (PBS, 10 mM, 9:1, v/v). The fluorescence of probe L is almost completely quenched upon the addition of Cu2+. The 2:1 stoichiometry of L-Cu2+ complex is confirmed by a Job's plot and ESI-MS analysis. More evidence about the interaction mechanism of L with Cu2+ is 1 HNMR titration data and density functional theoretical (DFT) studies. More importantly, the probe L with good cell permeability has been successfully applied to intra- cellular imaging of Cu2+ in A549 cells.