Facile fabrication of single-walled carbon nanotubes@cerium oxide composite sensing platform for ultrasensitive electrochemical analysis of methyl parathion

Abstract

We proposed a simple and feasible strategy to fabricate the nano-structured cerium oxide (CeO2) nanoparticles decorated single-walled carbon nanotubes networks (SWCNT@CeO2), which was utilized to fabricate the SWCNT@CeO2/GCE sensor for detecting methyl parathion (MP) with high sensitivity. SWCNT possessed the unique one-dimensional hollow nanostructure with excellent conductivity performance, which boosted the charge diffusion rate. CeO2 with good biocompatibility and high catalytic capacity could achieve the adsorption of MP molecules on the surface of sensing electrode due to the affinity of CeO2 nanoparticles towards the phosphate groups of MP. Furthermore, SWCNT could effectively make up for the inherent disadvantage of CeO2 nanoparticles in the term of electrical conductivity. The fabricated SWCNT@CeO2/GCE sensor achieved the ultrasensitive MP electrochemical analysis property (LOD: 9.12 nM). The satisfactory repeatability, reproducibility, anti-interference abilities were obtained at the fabricated sensor. Regarding the electrochemical detection of MP in real food samples, both satisfactory recovery rates of 87.68–107.31% and low RSD of 1.09–2.65% suggested the favorable application prospect of SWCNT@CeO2/GCE sensor in the field of pesticide residue analysis.