Hydroxyl-Functionalized Conjugated Porous Polymer for Effective Solid-Phase Microextraction of Pyrethroids followed by Gas Chromatographic Detection

Pyrethroid pesticide residues in fruits and vegetables pose a potential risk to human health. A hydroxyl-functionalized conjugated porous polymer (TP-DTO-CPP) was synthesized from 2,4,6-triacylated resorcinol and dithiooxamide and applied as a solid-phase microextraction (SPME) coating material for the preconcentration of pyrethroids. TP-DTO-CPP can interact with pyrethroids through pore filling, π stacking, and hydrogen bonding, thereby demonstrating a high extraction efficiency toward pyrethroids. A TP-DTO-CPP-coated SPME fiber coupled with gas chromatography-electron capture detection was developed for detecting pyrethroids. The method demonstrated good linearity for the pyrethroids in fruit and vegetable matrices across the concentration range of 0.34-1000 ng g^-1 (<i>R</i>² <i>></i> 0.9941). The limits of detection and quantification were 0.10-5.0 ng g^-1 and 0.34-17 ng g^-1, respectively. Spiked recoveries of pyrethroids from real samples ranged from 80.8% to 123%, with relative standard deviations ranging from 1.8% to 9.2%.