A ratiometric fluorescent probe for sensing hydrogen peroxide based on a hemicyanine–naphthol fluorophore

Abstract

The synthesis, properties and applications of a water-soluble boronate-functioned hemicyanine-naphthol hybrid as a novel ratiometric fluorescent sensor for hydrogen peroxide are presented. The dye displayed remarkable a colour change from pale orange (λ(em) = 590 nm) to pink (λ(em) = 690 nm) in the presence of H2O2, which could be rationalized by the chemoselective H2O2-mediated transformation of arylboronate to phenolate with high selectivity and a fast response (within 2 min). A good linear relationship (R(2) = 0.9951) was obtained with the H2O2 concentration ranging from 0 to 25 μM, with a limit of detection of 0.09 μM according to the signal-to-noise ratio (S/N = 3). The advantages of this fluorophore include easy modification, excellent aqueous solubility and superior photostability, and it has been applied to the detection of trace amounts of hydrogen peroxide in water samples.