AuNPs and CNTs embellished three-dimensional bloom-like α-Fe2O3 nanocomposites for highly sensitive electrochemical pesticides detection

Abstract

In this experimental study, a highly sensitive electrochemical acetylcholinesterase (AChE) biosensor for the detection of organophosphorus pesticides (OPs) based on three-dimensional α-Fe2O3 nanoflowers decorated with Au nanoparticles (AuNPs) and carbon nanotube (CNTs) (α-Fe2O3 NFs-AuNPs-CNTs) was developed. With the blooms structure, the α-Fe2O3 NFs not only provided an excellent microenvironment for the loading of AChE, but also increased the contact specific surface area. Meanwhile, AuNPs dispersed uniformly on the α-Fe2O3 nanosheets and CNTs further enhanced the conductivity of the nanocomposites. Under the optimized conditions, the biosensor was made to exhibit favorable linear relationship with the logarithm of the concentration of omethoate from 1 × 10−13-1 × 10−7 M, with the detection limit of 1.9 × 10−15 M. In addition, the biosensor also possessed good repeatability, stability and practicality, proved to be a valuable tool for the detection of pesticides in environment.