Ultrasensitive indirect electrochemical sensing of thiabendazole in fruit and water by the anodic stripping voltammetry of Cu2+ with hierarchical Ti3C2Tx-TiO2 for signal amplification

Abstract

The development of effective electrochemical methods for the determination of pesticide residues is highly desirable for food safety requirements. Herein, a novel electrochemical sensing strategy for indirect detection of thiabendazole (TBZ) was achieved by monitoring the anodic stripping peak signal change of media Cu²⁺ induced by a significant activity difference between active Cu²⁺ and inactive Cu²⁺-TBZ complexes. In this sensing system, a heterostructured Ti₃C₂T_x-TiO₂ composite synthesized via a simple in-situ-oxidization strategy is used as the electrode material to boost the anodic stripping peak signal. After optimizing various conditions, the developed sensor presents satisfactory analytical performance for TBZ assay with a linear range from 0.3 to 100.0 nM and a limit of detection as low as 0.1 nM (S/N = 3). Furthermore, the proposed sensing platform also exhibits outstanding anti-interference, repeatability, and stability, which is effective for the determination of TBZ in fruit and water samples.

Keywords: Complexation reaction; Indirect electrochemical sensing strategy; Thiabendazole; Ti(3)C(2)T(x) MXene; TiO(2).