An AIE and PET fluorescent probe for effective Zn(ii) detection and imaging in living cells

Abstract

A sensitive fluorescent probe L for Zn²⁺ with aggregation-induced emission (AIE) properties has been synthesized. The probe L exhibits specific selectivity and high sensitivity towards Zn²⁺ in EtOH/H₂O (4 : 1, v/v, HEPES = 20 mM, pH = 7.20) solvents, with the detection limit of 2.1 × 10⁻⁸ M. The potential sensing mechanism was analyzed via Job plot, MS and NMR titration, and the complexation ratio of the probe L and Zn²⁺ was 1 : 1. Furthermore, the as-prepared probe shows high sensitivity towards Zn²⁺ in a pH range of 4.8–12.0, combined with its wonderful cell permeability which ensures that it can work under physiological conditions and can image Zn²⁺ in living cells.