A new polyoxometalate/rGO/Pani composite modified electrode for electrochemical sensing of nitrite and its application to food and environmental samples

The reduced graphene oxide – polyaniline – Arsenomolybdate (rGO-Pani-AsM) composite modified glassy carbon electrode (GCE) interface has been demonstrated as a sensitive electrochemical interface for nitrite sensing. The synthesized composite has been characterized by spectroscopic and electrochemical techniques such as X-ray diffraction (XRD), Fourier transform Infra-red spectroscopy (FTIR), Raman spectroscopy, scanning electron microscopy (SEM), cyclic voltammetry (CV) and square wave voltammetry (SWV). The rGO-Pani-AsM composite exhibited higher oxidative current and reduced over potentials in the electrochemical oxidation of nitrite than bare glassy carbon electrode. The proposed sensor exhibited linearity in the concentration range 25–7500 μM with a limit of detection (LOD) of 10.71 μM and sensitivity of 0.803 μA μM−1 cm−2. The analytical utility of the proposed sensor has been examined by applying it to real sample analysis such as packed beverages, cucumber extract and water samples.