Simple method for preparing methyl parathion sensor based on nanoporous gold/MWCNTs electrodes

Abstract

A novel electrochemical sensor based on multi-walled carbon nanotubes modified nanoporous gold (NPG) electrode was built for the determination of methyl parathion. Multi-walled carbon nanotubes (MWCNTs) were used as a sorbent for solid-phase extraction (SPE) of methyl parathion and a good electrocatalytic material, whereas the NPG has attracted considerable attention owing to its unique properties: high surface-to-volume reaction, stability, high in-plane conductivity. A combination of SPE with square-wave voltammetric (SWV) analysis resulted in a fast, sensitive, and selective electrochemical method for determination of methyl parathion. Operational parameters, including the concentration of MWCNTs and pH of the methyl parathion solution have been optimised. The linear range for the detection of methyl parathion was from 1.0 × 10⁻⁷ g · mL⁻¹ to 1.0 × 10⁻⁵ g · mL⁻¹, whereas the detection limit was 4.8 × 10⁻⁸ g · mL⁻¹. The promising stripping voltammetric performances open new opportunities for the fast, simple, and sensitive analysis of methyl parathion in environmental and biological samples. These findings can lead to a widespread use of electrochemical sensors to detect methyl parathion.

Keywords:

• methyl parathion
• multi-walled carbon nanotubes
• nanoporous gold
• SWV

Acknowledgements

This work was supported by the National Natural Science Foundation of China (21105053), the National Basic Research Program of China (2012CB722606), and the Scientific and Technical Development Project of Qingdao (12-1-4-3-(4)-jch and 11-2-4-3-(8)-jch).