A covalent triazine framework as an oxidase mimetic in the luminol chemiluminescence system: application to the determination of the antioxidant rutin

It is found that a covalent triazine framework (CTF–1) (that was prepared from 1,4–dicyanobenzene) exhibits oxidase–like activity toward the oxidation of luminol with dissolved oxygen in alkaline condition to produce intense blue chemiluminescence (CL). The reaction follows Michaelis–Menten kinetics and shows strong specificity for luminol. Reactive oxygen species including ¹O₂, ^•OH and O₂^•− are testified to be involved in the reaction and responsible for the CL. The reaction was applied to the determination of the radical–scavenging activity of antioxidants, with rutin, kaempferol and ferulic acid serving as model scavengers. A sensitive CL method was developed for the determination of rutin based on its inhibitory effect on the reaction. The CL system gave a linear response to the concentration of rutin in the range of 0.03–0.25 μmol·L⁻¹ with a limit of detection of 0.015 μmol·L⁻¹. The practicability of the method was demonstrated by successful determination of rutin in tablets and in Flos Sophorae Immaturus.