IFE based nanosensor composed of UCNPs and Fe(II)-phenanthroline for detection of hypochlorous acid and periodic acid

Oxidizing ClO−and IO4−exist widely in environment and are closely related to the health of organisms. Accordingly, fast, sensitive, and direct detection of the two species is significant. Using IFE in UCNPs @PAA and Fe(II)-phenanthroline system, an elegant ratiometric fluorescent nanosensor, without noble metal nanoparticle, was designed for the detection of ClO−and IO4−. Fe(II)-phenanthroline complex is used as fluorescent absorber, which can quench green light of UCNPs with gradually varied extent depending on the concentration of Fe(II). The linear zone extends to 800 and 120 μmol/L while the detection limit is 1.30 and 0.58 μmol/L for NaClO and NaIO4, respectively. Finally, the nanosensor was successfully applied to detect NaClO and NaIO4spiked in milk, spring water, and tap water with good recoveries.