A Novel Electrochemical Sensor Based on MnO2/Sepiolite Nanocomposite for the Detection of Hydrogen Peroxide in Human Serum Samples

Background: The reliable and easy-to-operate detection of hydrogen peroxide (H2O2) has attracted extensive attention in the fields of biomedicine, food security, and environmental analysis. Objectives: In this work, a novel electrochemical method was proposed for H2O2 monitoring using a carbon paste electrode (CPE) modified with MnO2/sepiolite nanocomposite. Methods: MnO2/sepiolite material was characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) technique. The modified CPE was employed for the amperometric monitoring of H2O2 in human serum samples. Results: Electrochemical data showed that the MnO2/sepiolite-CPE displays a high peak current towards H2O2 oxidation. A linear range from 5 to 700 M and a low detection limit of 0.8 M for H2O2 were obtained with the proposed sensor. Besides, the electrode depicted excellent reproducibility and anti-interferant ability, promising the applicability of this electrochemical method in practical analyses. Conclusions: This work introduced a new and effective enzyme-lessH2O2 sensor based on theMnO2/sepiolite nanocomposite modified CPE. The suggested sensor showed good sensitivity for the rapid detection of H2O2 in a wide linear range with a low detection limit and satisfactory reproducibility, which made it practical for the analysis of hydrogen H2O2 in real samples.