A ratiometric fluorescent probe based on phenothiazine and quinazolinone for rapid detection of ClO− and its application

Abstract

A novel fluorescent probe (BPQ-1) with large conjugated system (phenothiazine was conjugated with quinazolinone) was synthesized. BPQ-1 showed a remarkable ratiometric fluorescence response to ClO⁻ within 10 s, and achieved large stokes shift (168 nm), high sensitivity (LOD = 16.7 nM) and excellent selectivity. Among the analytes to be detected, there is a significant change from bright yellow fluorescence to cyan fluorescence only when ClO⁻ is added to BPQ-1. Through density functional theory calculation and mass spectrometry experiments, the fluorescence response mechanisms of the BPQ-1 are given. In addition, BPQ-1 has been successfully applied to the detection of ClO⁻ in real water samples and test strips for detecting ClO⁻ with different concentrations have been prepared. In particular, the probe has been successfully applied to the fluorescence imaging of exogenous ClO⁻ in living cells.