In this study, a new automated magnetic micro solid-phase extraction was introduced. A Tygon tube was folded and fixed around the pole of a cylindrical magnet. Nanosized magnetic sorbents modified with diphenyldichlorosilane were uniformly immobilized on one side of the inner wall of the tube. Sample solution and desorption solvent were passed through the tube using a peristaltic pump. Four phenylurea herbicides (tebuthiuron, monolinuron, isoproturon, and monuron) were used as the model compounds to evaluate the method performance. HPLC-UV was used to separate and quantify the analytes. The effective parameters influencing the performance of the extraction process (i.e., extraction and desorption flow rates, eluent and sample volumes, type of eluent and sample ionic strength) were investigated. The limit of detection was 0.04 μg L-1 for all studied compounds. Calibration curves were linear in the range of 0.1-500 μg L-1 with a determination coefficient between 0.9988 and 0.9999. Intra-day, inter-day and batch-to-batch precisions expressed as relative standard deviation were less than 7%. Several environmental water samples were investigated to assess the applicability of the method for real sample analysis.

中文翻译：

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一种有效的配置，用于从水样品中自动磁性微固相萃取苯基脲除草剂，然后进行高效液相色谱分析。

在这项研究中，介绍了一种新的自动磁性微固相萃取。将Tygon管折叠并固定在圆柱磁铁的磁极周围。用二苯基二氯硅烷改性的纳米级磁性吸附剂均匀地固定在管内壁的一侧。使用蠕动泵使样品溶液和解吸溶剂通过试管。四种苯基脲除草剂（丁苯磺隆，单亚麻隆，异丙隆和莫隆）用作模型化合物，以评估方法的性能。HPLC-UV用于分离和定量分析物。研究了影响萃取过程性能的有效参数（即萃取和解吸流速，洗脱液和样品量，洗脱液类型和样品离子强度）。检测极限为0。所有研究的化合物均为04μgL-1。校准曲线在0.1-500μgL-1范围内呈线性，测定系数在0.9988至0.9999之间。以相对标准偏差表示的日内，日间和批间精度小于7％。对几个环境水样品进行了研究，以评估该方法在实际样品分析中的适用性。