One-pot fabrication of Fe-doped carbon nitride nanoparticles as peroxidase mimetics for HO and glucose detection.

Iron-doped carbon nitride nanoparticles (Fe-CNNPs) were prepared from citric acid, urea and ferric chloride through a convenient one-pot solvothermal method. Oleic acid was used as the reaction medium. The morphology and chemical composition of the obtained Fe-CNNPs were characterized by multiple methods including transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FT-IR). It is interesting to find that the Fe-CNNPs showed higher catalytic activity than horseradish peroxidase (HRP), and tetramethylbenzidine (TMB) can be catalytically oxidized in the presence of HO to produce a color change in aqueous solution. As HO can be generated in the oxidation process of glucose catalyzed by glucose oxidase (GOD), a novel sensitive method for the detection of glucose with a limit of detection (LOD) of 0.29 μM has been developed combined with the catalytic properties of GOD and Fe-CNNPs. The Fe-CNNPs with peroxidase mimetics activity may have potential applications in biotechnology field.