Fluorometric analysis of chlorite via oxidation of 9-anthracenecarboxaldehyde

We investigated a simple fluorescence signaling method for the convenient analysis of a practical oxidant—chlorite—via the oxidation of 9-anthracenecarboxaldehyde to the corresponding carboxylic acid. 9-Anthracenecarboxaldehyde exhibited a marked ratiometric fluorescence signaling toward chlorite through manipulating its aggregation-induced emission property. The probe showed high chlorite-selectivity over other oxychlorine species as well as common metal ions, anions, and oxidants. Interference from a closely related oxidant, hypochlorite, was efficiently removed using DMSO as a scavenger. The proposed probe also exhibited a prominent ratiometric response through changes in UV–vis absorption behavior. Among the tested aromatic aldehydes (naphthaldehydes, anthracenecarboxaldehyde, and pyrenecarboxaldehyde), anthracene-based carboxaldehyde exhibited the most pronounced signaling contrast and the fastest signaling speed. The detection limit of chlorite determination was found to be 1.1 × 10–7 M. Exploitation of the probe for the convenient analysis of chlorite in tap water via a recovery test was conducted.