Free‐enzymatic Indirect Detection of Malathion by SiC@CuO‐NPs Composite Nanomaterial Modified Glassy Carbon Electrode

Abstract

AbstractWe prepared a highly sensitive electrochemical sensor for the free‐enzymatic indirect detection of malathion. The electrochemical sensor was based silicon carbide and copper oxide nanocomposite material. The structural and morphological properties of the SiC@CuO‐NPs nanocomposite was characterized by scanning electron microscopy (SEM) and X‐ray diffraction (XRD). SiC‐NPs has the function of malathion pre‐concentration and SiC@CuO‐NPs nanocomposite was noted to possess high affinity towards malathion, thus the redox reaction of CuO could be hindered. This feature was utilized to design as a simple strategy for electrochemical detection of malathion. Electrochemical detection of malathion was investigated via cyclic voltammetry (CV), differential pulse voltammetry (DPV), respectively. Under the optimized experimental conditions, the inhibition rate displays a good linear relationship with the concentration of malathion, the linear range is 0.03 nM∼3.0 nM, and the detection limit is 0.01 nM (S/N=3). In addition, the sensor exhibits good selectivity, stability and reproducibility, and has been successfully used in the detection of malathion in actual water samples with recoveries between 99.33 % and 106.6 %, which is satisfactory experimental results.