Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, P.O. Box 1009, Xiamen, Fujian 361005, PR China.
Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystem, Fujian Provincial Key Laboratory for Coastal Ecology and Environmental Studies, College of the Environment and Ecology, Xiamen University, P.O. Box 1009, Xiamen, Fujian 361005, PR China.
J Chromatogr A. 2020 Feb 22;1613:460672. doi: 10.1016/j.chroma.2019.460672. Epub 2019 Nov 4.
In the present study, porous monolith-based magnetism-reinforced in-tube solid phase microextraction (MB-MR/IT-SPME) was first introduced to concentrate sulfonylurea herbicides (SUHs). To realize the effective capture of SUHs, a monolithic capillary microextraction column (MCMC) based on poly (vinylimidazole-co-ethylene dimethacrylate) polymer doped with FeO magnetic nanoparticles was in-situ synthesized in the first step. After that, the MCMC was twined with a magnetic coil which was employed to carry out variable magnetic field during adsorption and desorption procedure. Various important parameters that affecting the extraction performance were inspected in detailed. Results well indicated that exertion of magnetic field in the whole extraction procedure was in favor of the capture and release of the studied SUHs, with the extraction efficiencies increased from 36.8-58.1% to 82.6-94.5%. At the same time, the proposed MB-MR/IT-SPME was online combined to HPLC with diode array detection (HPLC/DAD) to quantify trace levels of SUHs in water and soil samples. The limits of detection (S/N = 3) for water and soil samples were in the ranges of 0.030-0.15 μg/L and 0.30-1.5 μg/kg, respectively. The relative standard deviations (RSDs) for intra- and inter-day variability were both less than 10%. Finally, the introduced approach was successfully applied to monitor the low contents of studied SUHs in environmental water and soil samples. Satisfying fortified recovery and precision were achieved.
在本研究中，首次引入基于多孔整体式的磁强化管内固相微萃取（MB-MR/IT-SPME）来浓缩磺酰脲类除草剂（SUHs）。为了实现 SUHs 的有效捕获，在第一步中，我们在原位合成了一种基于聚（乙烯亚胺-co-二甲基丙烯酸乙酯）聚合物的整体式毛细管微萃取柱（MCMC），其中掺杂了 FeO 磁性纳米粒子。之后，将 MCMC 缠绕在一个磁性线圈上，在吸附和解吸过程中利用该线圈施加可变磁场。详细考察了影响萃取性能的各种重要参数。结果表明，在整个萃取过程中施加磁场有利于研究 SUHs 的捕获和释放，萃取效率从 36.8-58.1%提高到 82.6-94.5%。同时，将所提出的 MB-MR/IT-SPME 与二极管阵列检测（HPLC/DAD）在线联用，用于定量水和土壤样品中痕量的 SUHs。水和土壤样品的检出限（S/N=3）分别在 0.030-0.15μg/L 和 0.30-1.5μg/kg 的范围内。日内和日间变异的相对标准偏差（RSDs）均小于 10%。最后，该方法成功应用于监测环境水样和土壤样品中研究的 SUHs 的低含量。获得了令人满意的加标回收率和精密度。
