Copper (I)-Based Metallo-Supramolecular Polymer for Nonenzymatic Electrochemical Detection of Nitrite

Abstract

The electrochemical detection of nitrite, known for its environmental and health hazards, has been a focal point of research. A novel Cu(I)-based metallo-supramolecular polymer (SMP) (polyCu) was developed for nitrite detection using a symmetrical hexadentate terpyridine ligand[4’,4”“-(1,4-phenylene) bis(2,2’:6’,2”-terpyridine)] ligand in 1:1 ratio. The Cu(I) complexation with the ligand was confirmed through UV-Vis spectroscopy, and the prepared polyCu polymer was characterized using field-emission scanning electron microscopy (FESEM) and energy dispersive X-ray spectroscopy (EDS) techniques. The viscosity measurement of polyCu was utilized to calculate its molecular weight using Mark–Houwink-Sakurada equation. Electrochemical analysis, including cyclic voltammetry (CV) and differential pulse voltammetry (DPV), revealed excellent activity in nitrite sensing, with a well-defined peak. DPV exhibited a linear range of 1–500 μM and a low limit of detection (LOD) of 2.378 μM. The sensing mechanism was predicted based on the literature review. The polyCu_GCE demonstrated high selectivity, stability, and repeatability, making it a reliable electrocatalyst. Real sample analysis affirmed its practical applicability, positioning the sensor as a cost-effective and dependable system for nitrite sensing.