RESUMO
Precisely detecting trace pesticides and their residues in food products is crucial for ensuring food safety. Herein, a high-performance electrochemical sensing platform was developed for the detection of carbendazim (CBZ) using Co,N co-doped hollow carbon nanocage@carbon nanotubes (Co,N-HC@CNTs) obtained from core-shell ZIF-8@ZIF-67 combined with a poly(3,4-ethylenedioxythiophene) (PEDOT) molecularly imprinted polymer (MIP). The Co,N-HC@CNTs exhibited excellent electrocatalytic performance, benefitting from the synergistic effect of CNTs that provide a large specific surface area and excellent electrical conductivity, Co,N co-doped carbon nanocages that offer high electrocatalytic activity and hollow nanocage structures that ensure rapid diffusion kinetics. The conductive PEDOT-MIP provided specific binding sites for CBZ detection and significantly amplified the detection signal. The sensor showed superior selectivity for CBZ with an extremely low detection limit of 1.67 pmol L-1. Moreover, the method was successfully applied to detect CBZ in tomato, orange and apple samples, achieving satisfactory recovery and accuracy, thus demonstrating its practical feasibility.