A highly specific benzothiazole-based Schiff base for the ratiometric detection of hypochlorite (ClO−) ions in aqueous systems: a real application in biological imaging

Abstract

This study describes the rational development and synthesis of a benzothiazole-salicylaldehyde Schiff base probe 1. This probe is designed to function as a ratiometric fluorescent probe specifically for detecting ClO⁻ ions, utilizing the imine bond as the fluorophore unit. Upon interaction with ClO⁻ ions, probe 1 exhibits a redshift in its absorption spectrum from 435 nm to 450 nm. Moreover, in its emission spectrum, there is a ratiometric emission enhancement observed at 610 nm, providing a clear indication of the presence of ClO⁻ ions. The sensitivity of probe 1 for detecting ClO⁻ ions is quantified, revealing a lowest detection limit of 5.5 μM, indicating its potential for sensitive detection even at low concentrations of ClO⁻ ions. Additionally, it has been successfully utilized for biological imaging purposes, demonstrating low cytotoxicity, which is crucial for its applicability in biological systems.