Electrochemical Determination of Hydrogen Peroxide Using a Horseradish Peroxidase (HRP) Modified Gold–Nickel Alloy Nanoparticles Glassy Carbon Electrode (GCE)

Abstract

Au₂Ni₁ alloy nanoparticles (NPs) were synthesized by a reverse microemulsion procedure and the structure, morphology, and composition were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and energy-dispersive X-ray spectroscopy (EDS). The results showed that the synthesized NPs were random alloys with a Au/Ni atom ratio of 2:1 with a face-centered cubic (fcc) structure and average diameters of 8 ± 2 nm. A novel hydrogen peroxide (H₂O₂) sensor was constructed using horseradish peroxidase (HRP) modified by the Au₂Ni₁ alloy NPs. The sensor properties were characterized by cyclic voltammetry (CV) and amperometry in H₂O₂ solution. The results demonstrate that the sensor exhibited good performance for H₂O₂ in phosphate buffer saline at pH 7.2. The detection limit was 2.12 × 10⁻⁸mol/L with a linear correlation coefficient (R²) of 0.99647 with good stability and reproducibility.

Keywords:

• Amperometry
• cyclic voltammetry (CV)
• horseradish peroxidase (HRP)
• gold–nickel (Au₂Ni₁) alloy nanoparticles (NPs)
• hydrogen peroxide (H₂O₂)

Additional information

Funding

This work was supported by the National Natural Science Foundation of China by Grants 31772019 and 31871811, the Key Project of the Natural Science Foundation of Tianjin by Grant 10JCZDJC23600, and Natural Science Foundation of Tianjin by Grant 18JCYBJC89900.