Magnetic solid‐phase extraction (MSPE) employing a metal–organic framework (Fe₃O₄@UiO‐66‐OH) combined with high‐performance liquid chromatography was developed for the determination of trace diuretics in urine. The structure and properties of Fe₃O₄@UiO‐66‐OH were investigated using X‐ray diffraction, infrared spectroscopy, scanning electron microscopy and vibrating sample magnetometry. Magnetic solid‐phase extraction conditions, such as adsorbent amount and solution pH, were optimized using response surface methodology. Under the optimal conditions, the method resulted in excellent linearity with a high correlation coefficient (r > 0.99), satisfactory intraday repeatability (1.78–2.99%), low limits of detection (0.08–0.23 ng/ml), and good recoveries in urine samples (between 93.5 and 103%). Fe₃O₄@UiO‐66‐OH based on MSPE is a novel pretreatment technique for the detection of trace diuretics in urine.

中文翻译：

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使用HPLC结合基于金属有机骨架的磁性固相萃取法测定人尿中的利尿剂。

磁性固相萃取（MSPE）采用金属-有机骨架（Fe ₃ O ₄ @ UiO-66-OH）与高效液相色谱法相结合，用于测定尿液中的微量利尿剂。用X射线衍射，红外光谱，扫描电子显微镜和振动样品磁力分析法研究了Fe ₃ O ₄ @ UiO-66-OH的结构和性能。使用响应面方法优化了固相萃取的磁性条件，例如吸附剂的量和溶液的pH。在最佳条件下，该方法具有出色的线性度和高相关系数（r> 0.99），令人满意的日内重复性（1.78–2.99％），低检测限（0.08–0.23 ng / ml）和尿液样品中良好的回收率（93.5至103％）。基于MSPE的Fe ₃ O ₄ @ UiO-66-OH是检测尿中微量利尿剂的一种新型预处理技术。