Open Access
Highlights
• A ratiometric fluorescent probe was constructed for hypoxanthine detection.
• The method was based on the enzyme and fluorescence characteristics of Co-doped-g-C3N4.
• The ratiometric fluorescent probe was sensitive, accurate, and reliable.
Abstract
A ratiometric fluorescent probe for hypoxanthine (Hx) detection was established based on the mimic enzyme and fluorescence characteristics of cobalt-doped graphite-phase carbon nitride (Co doped g-C3N4). In addition to emitting strong fluorescence, the peroxidase activity of Co doped g-C3N4 can catalyze the reaction of O-phenylenediamine and H2O2 to produce diallyl phthalate which can emit yellow fluorescence at 570 nm. Through the decomposition of Hx by xanthine oxidase, Hx can be indirectly detected by the generating hydrogen peroxide based on the measurement of fluorescent ratio I (F570/F370). The linear range was 1.7–272.2 mg/kg (R2 = 0.997), and the detection limit was 1.52 mg/kg (3σ/K, n = 9). The established method was applied to Hx detection in bass, grass carp, and shrimp, and the data were verifi ed by HPLC. The result shows that the established probe is sensitive, accurate, and reliable, and can be used for Hx detection in aquatic products.