Development of a novel electrochemical nitrite sensor based on Zn‐Schiff base complexes

A novel electrochemical sensor for the determination of nitrites based on the modified screen-printed electrode (SPCE) by Zn-bidentate Schiff base complexes (ZnLX2) is presented. ZnLX2 complexes have been synthesized and characterized using several morphological and microstructural techniques such as scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and fourier transformed-infrared (FT-IR) spectroscopy. Cyclic voltammetry (CVs) proved the good electrochemical performances of the ZnLX2/SPCE for nitrite ions determination. The influence of pH, scan rate, nitrite concentration, and interfering ions was investigated. After optimization of the operating parameters, the developed ZnLX2/SPCE sensor displayed two linear relationships between response current and nitrite concentration in the overall range 2-4838 mu M and a lower detection limit estimated to be 0.78 mu M based on 3 sigma/m. Finally, the analytical application of the developed sensor was evaluated to quantify nitrite in a real sample of mineral water. Results obtained demonstrate that the ZnLX2/SPCE electrochemical sensor provided an effective tool for the detection of nitrite ions.