Bifunctional fluorescent probe for fluoride and copper(Ⅱ) based on perylene diimide derivative and its application in cell imaging

Abstract

A bifunctional fluorescent probe P1 based on perylene diimide derivative (PDI) was developed, demonstrating high sensitivity and selectivity for the rapid detection of fluoride (F-) and copper (Cu2+). The fluorescence of P1 was quenched upon interaction with F- and enhanced upon interaction with Cu2+. The concentration ranges for fluorescent detection of F- and Cu2+ are 0 ∼ 4 × 10-5 M and 0 ∼ 2.4 × 10-5 M, respectively. The stoichiometry of the complex formed between Cu2+ and P1 or F− and P1 was 1:1. The probe displays detection limits of 0.16 and 0.21 μM and binding constants (Ksv) of 3.92 × 104 and 1.72 × 104 M−1 for the detection of F- and Cu2+, respectively. The sensing mechanism and binding mode of P1 with F- and Cu2+ were investigated. The fluorescence quenching/enhancement of P1 was controlled by a photoinduced electron-transfer (PET) process. Furthermore, the ability of the probe to detect intracellular F- and Cu2+ was assessed using cell imaging techniques.