Integrated substrate-nanozyme-adsorbent tri-functional sensor: sensitive detection of lambda-cyhalothrin residues in agricultural products.

Abstract

Lambda-cyhalothrin (LC), a persistent pesticide with health risks, requires rapid and reliable monitoring methods. Herein, multifunctional materials (MIPs@MIL-88-Cu) were developed by incorporating molecular imprinting technology into Cu-doped MIL-88 nanozyme synthesis, with terephthalic acid serving as both structural backbone and self-supplying substrate. This method successfully realized the integration of substrate, nanozyme and adsorbent functionalities within a single system. LC specifically occupied the imprinted cavities, which inhibited the nanozyme activity and quenched the fluorescence through electron transfer, thus enabling specific recognition of LC. The developed method exhibited a linearity (50.0-1000 ng L-1), with a limit of detection of 15.0 ng L-1. Furthermore, it also simplified both the synthesis and detection processes. The practical application potential of the developed method was validated using spiked vegetable and fruit sample matrix, achieving satisfactory recoveries and low relative standard deviations. This study offered innovative insights into constructing sensitive recognition sensors.