Surface Optimization of Glassy Carbon Electrode with Graphitized and Carboxylated Multi-Walled Carbon Nanotubes@β‐Cyclodextrin Nanocomposite for Electrochemical Determination of Methyl Parathion

We reported a simple and low-cost ultrasound-assisted preparation of β‐cyclodextrin/graphitized and carboxylated multi-walled carbon nanotubes (β-CD/GR-MWCNTs-COOH) nanocomposite, which was used to modify the glassy carbon electrode (GCE) to fabricate the β-CD/GR-MWCNTs-COOH/GCE sensor for the determination of methyl parathion (MP). The phase structure and surface morphology of β-CD/GR-MWCNTs-COOH nanocomposite was characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). For this nanocomposite, GR-MWCNTs-COOH had high electrical conductivity, large specific surface area, and good hydrophilicity; β-CD promoted the uniform dispersion of GR-MWCNTs-COOH and possessed excellent molecular recognition ability for organic molecules. Electrochemical measurements showed that the β-CD/GR-MWCNTs-COOH/GCE sensor presented good MP determination performance with high peak current response due to the synergistic effect of β-CD and GR-MWCNTs-COOH. Under the optimal condition, the fabricated β-CD/GR-MWCNTs-COOH/GCE sensor showed a low limit of detection of 0.027 μM in linear MP concentration range of 0.01-15 μM. This work has a certain promoting significance for the development of high-performance MP electrochemical sensor.