Co3O4nanoparticles-enhanced luminol chemiluminescence and its application in H2O2 and glucose detection

Abstract

In this study, Co₃O₄ nanoparticles were synthesized by a hydrothermal method and characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). The as-prepared Co₃O₄ nanoparticles were used to amplify a weak chemiluminescence (CL) of a luminol-H₂O₂ system. The results of UV-visible absorption and CL spectra showed that the CL luminophor was 3-aminophthalate, indicating that the CL enhancement of the luminol-H₂O₂ system was attributed to the intrinsic catalytic effect of Co₃O₄ nanoparticles acting as the electron transfer accelerators and radical generation proliferators. Based on the H₂O₂ concentration dependence of the catalytic activity of Co₃O₄ nanoparticles, a simple, sensitive and relatively selective CL assay for H₂O₂ was constructed. Under the optimized conditions, a linear relationship was obtained between the CL intensity and H₂O₂ concentration in the range of 1.0 × 10⁻⁸–1.0 × 10⁻⁵ mol L⁻¹ with a detection limit of 1.1 × 10⁻⁹ mol L⁻¹. When combined with the glucose oxidase-catalyzed oxidation reaction, the sensitive detection of glucose could be realized. The linear range for glucose was from 1.0 × 10⁻⁷ to 1.0 × 10⁻⁵ mol L⁻¹ with a detection limit of 8.0 × 10⁻⁸ mol L⁻¹. This proposed method has been successfully applied to the determination of H₂O₂ in rain water and glucose in serum samples.