A Pitaya-Inspired Modular Cylindrical MOF-Based Capsule Design for Pesticide Signal Probes
Wenwen Jia, Jian Zhang, Ruiqing Fan, Ke Zhu, Shuang Gai, He Tao, Chengshan Ji, Huimin Nai, Yulin Yang
Abstract
Excessive use of pesticides has brought about serious environmental risks worldwide that pose significant harm for human health. Herein, a series of metal–organic framework (MOF)-based gel capsules with a pitaya-like core–shell structure are constructed through a green polymerization strategy for pesticide detection and removal, namely ZIF-8/M-dbia/SA (M = Zn, Cd). Significantly, the ZIF-8/Zn-dbia/SA capsule exhibits sensitive detection of alachlor, a representative pre-emergence acetanilide pesticide, with a satisfactory detection limit of 0.23 μM. In addition, the MOF-based gel capsules can be extended to a universal visual platform for the noninvasive detection of pesticide residues with various MOFs, such as Eu-MOF, Tb-MOF, and Cu-MOF, and participating dye. Similar to pitaya, the ordered porous structure of MOF in ZIF-8/Zn-dbia/SA capsules offers cavity and open sites for removing pesticide from water with the maximum adsorption amount q max of 61.1 mg·g –1 toward alachlor in a Langmuir model. Thereby, this work presents the universality of gel capsule self-assembly technologies, including the well-preserved visible fluorescence area and porosity of the different structurally diverse MOFs, offering an ideal strategy for water decontamination and food safety control fields.