Non-enzymatic potentiometric malathion sensing over chitosan-grafted polyaniline hybrid electrode

Non-enzymatic electrochemical malathion sensing has been demonstrated over chitosan-grafted polyaniline (CHIT-g-PANI)-based electrode. Structural, morphological, and physical properties of electrode were investigated by Fourier transform infrared (FTIR) spectrometer, X-ray diffraction (XRD), scanning electron microscope (SEM), thermal analysis (TGA), and other relevant ASTM methods. The obtained result suggests the formation of porous hybrid matrix with better free complexing group, electrical conductivity, and thermal stability due to rearrangement of molecular structure and crystallinity. Further, CHIT-g-PANI-based electrode was used for potentiometric sensing of malathion (MLT) in tomato juice by monitoring induced potential due to surface interaction between MLT and CHIT-g-PANI-based electrode. The observed sensing parameters are sensing range 62.5 to 2.0 µM, sensitivity 2.26 mV µM−1 cm−2, limit of detection 3.8 µM, response time 8.0 min, and recovery time 30 s. On the basis observed results a charge transferring, weak surface complexation-based sensing mechanism was proposed in fruits and vegetables in competitive and cost-effective manner.