Fabrication of spinel NiCoO nanoflowers by simple hydrothermal method for effective electrochemical detection of NO in processed food sample.

This study introduces a novel, cost-effective, highly sensitive electrochemical sensor for detecting nitrite (NO) in processed food samples. The sensor was developed by fabricating spinel NiCoO nanoflowers (NCO) using a hydrothermal method. Various characterization techniques, including XRD, FT-IR, XPS, HR-SEM, EDX, and HR-TEM, were used to analyze the structure and morphology of NCO. The obtained NCO exhibited a particle size of ∼16 nm and a flowered shape. Electrochemical impedance spectroscopy (EIS) was used to assess the electron-transfer properties. Cyclic voltammetry (CV) and chronoamperometry (CA) were employed to explore the electrocatalytic performance, revealing a high surface area and remarkable activity. The NCO electrode exhibited a remarkable sensitivity 44.16 μA mM cm at low concentrations and 33.51 μA mM cm at higher concentrations and a low detection limit of 0.99 μM. It is worth noting that the sensor displayed excellent reproducibility and repeatability, with relative standard deviation (RSD) values of 1.06 % and 1.37 %, respectively. Furthermore, the fabricated sensor was successfully applied for the detection of NO in milk, oranges, apple juice, wastewater, and processed foods such as chicken and sausage. The obtained results indicate that the proposed sensor is a promising candidate for practical NO detection applications.