Electroanalytical performance of hierarchical nanostructures of MgCo <sub>2</sub> O <sub>4</sub> on reduced graphene oxide modified screen-printed electrode for the sensitive determination of Sudan I
Hadi Beitollahi, Somayeh Tajik, Fariba Garkani Nejad, Mohammad Bagher Askari, Parisa Salarizadeh
Abstract
The present work reports the synthesis of MgCo2O4-rGO nanohybrid by a simple method. The nanohybrid was characterised by XRD, Raman spectroscopy, EDX, SEM, and TEM. An effective electrochemical sensing platform to detect Sudan I based on MgCo2O4-rGO nanohybrid modified screen-printed electrode (MgCo2O4-rGO/SPE) is reported. Electrocatalytic sensing of Sudan I is carried out using cyclic voltammetry (CV), linear sweep voltammetry (LSV), chronoamperometry (CHA) as well as differential pulse voltammetry (DPV) measurements. Interestingly, this newly developed sensor showed greater peak currents with the decreased anodic potential than that of the bare SPE. The modified electrode demonstrated distinctive electrocatalytic activities to detect Sudan I with the longer linear response range between 0.04 and 580.0 µM, low limit of detection (LOD) of 9.0 nM, and high sensitivity of 0.0838 µA µM−1. In addition, MgCo2O4-rGO/SPE sensor exhibited excellent electrochemical stability, repeatability and reproducibility for Sudan I detection. Analytical utility of our method revealed acceptable detection outputs for Sudan I. Therefore, it could be concluded that this sensor (MgCo2O4-rGO/SPE) exhibited very good electrochemical behaviour for electrochemical detection of Sudan I oxidation.