Abstract

A novel magnetic solid-phase extraction technique coupled to ultraperformance liquid chromatography has been developed for separation and preconcentration of four sulfonylurea herbicides (sulfosulfuron, bensulfuron-methyl, pyrazosulfuron-ethyl and halosulfuro-methyl) in aqueous samples. The key point of this method was the application of a novel magnetic nanomaterial that composed of a low eutectic solvent as a shell coated on the magnetic core modified by polydopamine. The extensive active sites outside the low eutectic solvent can effectively adsorb the target herbicide in the extraction process. The obtained magnetic adsorbent was characterized with fourier transform infrared spectrometry, scanning electron microscopy and vibrating sample magnetometer. The influence parameters relevant to this method were optimized. Under the optimum conditions, good linearities could be obtained within the range of 1.0–200 μg L⁻¹ for all analytes, with correlation coefficients ≥0.9908. The limit of detections of the method was between 0.0074 and 0.0100 μg L⁻¹ and the relative standard deviations were 1.1–3.6%. The enrichment factor is 66.6. In the final experiment, the proposed method was successfully applied to the analysis of sulfonylurea herbicides residue in environment and drinking-water samples, and the obtained recoveries were between 70.6% and 109.4%.

中文翻译：

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胆碱基低共熔溶剂修饰的磁性聚多巴胺用于磁性固相萃取水样中磺酰脲类除草剂

摘要

已经开发了一种新颖的磁性固相萃取技术与超高效液相色谱相结合，用于分离和预浓缩水溶液样品中的四种磺酰脲类除草剂（磺磺隆，苄磺隆，甲基吡唑磺隆，乙基和卤代磺酰甲基）。该方法的重点是应用一种新型的磁性纳米材料，该材料由低共熔溶剂组成，并作为外壳包覆在聚多巴胺修饰的磁芯上。低共熔溶剂之外的广泛活性位点可以在提取过程中有效吸附目标除草剂。用傅立叶变换红外光谱，扫描电子显微镜和振动样品磁强计对所得的磁性吸附剂进行表征。优化了与此方法有关的影响参数。在最佳条件下^-1对于所有分析物，相关系数≥0.9908。该方法的检出限在0.0074至0.0100μgL ^-1之间，相对标准偏差为1.1–3.6％。富集系数为66.6。在最终实验中，该方法成功地用于环境和饮用水样品中磺酰脲类除草剂残留的分析，回收率在70.6％至109.4％之间。