Yang Mei, Zhang Pengling, Kong Qidi, Sun Zhanyu, Li Zhongyue
School of Environmental and Material Engineering, Yantai University, Yantai, 264005, Shandong, China.
Mikrochim Acta. 2025 Jul 9;192(8):490. doi: 10.1007/s00604-025-07360-1.
Two hydrophobic covalent organic frameworks (COFs), BTT-TAPA-COF and BTT-TAPB-COF, were synthesized using benzotrithiophene (BTT), a fused heterocyclic building block. These COFs exhibited high porosity (BET surface areas of 763 and 1531 m/g) and strong hydrophobicity (contact angles of 118.5° and 127.5°). BTT-COFs were coated onto stainless-steel fibers and employed in solid-phase microextraction (SPME) coupled with GC-MS for pyrethroids detection in tea. Direct immersion (DI-SPME) achieved 200-fold higher extraction efficiency than headspace (HS-SPME). Epoxy resin was identified as the optimal adhesive for fiber preparation. The method demonstrated dual linear dynamic ranges for each analyte, with correlation coefficients (R) ranging from 0.9852 to 0.9999 and LODs as low as 0.002 ng·L⁻. Bifenthrin (BIF) and λ-cyhalothrin (CYH) were detected in all tested tea samples, at concentrations ranging from 7.9 - 98.2 ng·L⁻ and 1.2 - 4.2 ng·L⁻, respectively. The method exhibited satisfactory recoveries from 81.1% to 125.8%. This study highlights the potential of hydrophobic COFs as high-performance SPME materials for sensitive and reliable pesticide residue determination in food safety monitoring.
使用稠合杂环结构单元苯并三噻吩（BTT）合成了两种疏水性共价有机框架（COF），即BTT-TAPA-COF和BTT-TAPB-COF。这些COF表现出高孔隙率（BET表面积分别为763和1531 m²/g）和强疏水性（接触角分别为118.5°和127.5°）。将BTT-COF涂覆在不锈钢纤维上，并用于与气相色谱-质谱联用的固相微萃取（SPME）中，以检测茶叶中的拟除虫菊酯。直接浸入式（DI-SPME）的萃取效率比顶空式（HS-SPME）高200倍。环氧树脂被确定为纤维制备的最佳粘合剂。该方法对每种分析物都显示出双线性动态范围，相关系数（R）在0.9852至0.9999之间，检测限低至0.002 ng·L⁻¹。在所有测试的茶叶样品中均检测到联苯菊酯（BIF）和高效氯氟氰菊酯（CYH），浓度分别为7.9 - 98.2 ng·L⁻¹和1.2 - 4.2 ng·L⁻¹。该方法的回收率在81.1%至125.8%之间，令人满意。本研究突出了疏水性COF作为高性能SPME材料在食品安全监测中灵敏可靠地测定农药残留的潜力。
