Electrochemical detection of monosodium glutamate in foodstuffs based on Au@MoS2/chitosan modified glassy carbon electrode

We report an amperometric immunosensor for the detection of monosodium glutamate (MSG) using a glassy carbon electrode modified with gold nanoparticle decorated on a molybdenum disulfide/chitosan (Au@MoS 2 /Ch) nanocomposite. In the present detection technique, Au@MoS 2 /Ch was used as a conductive matrix and anti-glutamate antibody was immobilized on to its surface via carbodiimide coupling method. Chemical and morphological attributes of the various components of the immunosensor were confirmed by UV– vis spectroscopy, SEM, TEM and XRD analysis. Electrochemical characterizations were carried out by CV, DPV and EIS. Overall results showed the effective fabrication of highly conductive Au@MoS 2 /Ch nanocomposite for sensitive electrochemical detection of MSG. A linear relationship was perceived between the change in current and concentration of MSG. The relationship was found to be consistent in the detection range of 0.05–200 µM. Statistical validation of the assay showed limit of detection and limit of quantification values as 0.03 and 0.1 µM, respectively (R 2 = 0.99).