Fluorometric analysis of periodate based on the oxidation of 2-acetylnaphthol phenylselenoether: Application to the assay of regenerated periodate

Despite its utility as an oxidant, periodate is potentially toxic; therefore, simple methods with high sensitivity and selectivity are required for periodate determination. Herein, we report a novel periodate signaling probe, 2-acetylnaphthol phenylselenoether (PI-1), synthesized by the reaction of 2-acetyl-6-naphthol with phenylselenyl chloride. In the presence of periodate, the fluorescence emission wavelength of the designed probe changed significantly from 566 to 482 nm. The periodate signaling of PI-1 was due to the oxidative transformation of 2-acetylnaphthol phenylselenoether to the corresponding selenoxide derivative, as verified by 1H NMR spectroscopy and high-resolution mass spectrometry. An analysis of the signaling behavior of PI-1 using the fluorescence intensity ratio (I482/I566) confirmed that PI-1 exhibited high selectivity toward periodate over representative anions, metal ions, and oxidants. Furthermore, the presence of common anions and metal ions as background had no effect on periodate signaling. Notably, periodate signaling by PI-1 was accomplished in 15 min with high sensitivity (detection limit: 7.0 × 10–8 M, 13 ppb). As a practical application of the developed probe, a convenient fluorometric assay for regenerated periodate was demonstrated.