Arefeh Gorgij - Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
Hamid Ahmar - Department of Chemistry, Faculty of Science, University of Zabol, Zabol, Iran
Laleh Adlnasab - Department of Chemistry, Faculty of Chemistry and Petrochemical Engineering, Standard Research Institute, Karaj, Iran

Hydrogen peroxide (H2O2) is widely used in food, medicine, cosmetics, industry, and water treatment applications [1-2]. It can be toxic at higher concentration because of the oxidizing and corrosive nature. In this work, a novel electrochemical sensor based on Cu/Fe layered double hydroxide@Fe3O4 nanoparticles has been successfully fabricated and used to H2O2 detection.The prepared LDH nanocomposite was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), cyclic voltammetry (CV), and differential pulse voltammetry (DPV). Then, the LDH nanocomposite was immobilized on glassy carbon electrode and its electrocatalytic activity for H2O2 reduction was studied. Factors which affect the electrocatalytic activity (modifier amount, pH of solution, and analysis time) have been investigated. Under the optimized conditions, the H2O2 reduction current was linear to its concentration within the range of 10 ‒ 400 μM, and the detection limit was found to be 3 μM (S/N = 3). Finally, the prepared sensor has been successfully applied to determine the H2O2 content in human urine samples