Graphene-like two-dimensional transition metal dichalcogenides such as MoS₂, MoSe₂, MoTe₂, NbS₂, NbSe₂, WS₂, WSe₂, TaS₂ and TaSe₂ are emerging as promising new-generation materials because of their basic properties complementing those of graphene in practical applications. In this study, graphene-like MoS₂-modified magnetic carbon-dot nanoflowers (MoS₂@Fe₃O₄@C-dot NFs) were synthesized via a simple and green hydrothermal synthesis procedure. Carbon dots (C-dots) were obtained from cow's milk by a very simple one-step hydrothermal synthesis method. Owing to the fact that the sandwich layers of MoS₂ provide sufficient and effective intermediate layer spaces, a large number of magnetic C-dots can easily enter these spaces between the layers. A MoS₂ aqueous solution has good chemical stability and dispersibility in acidic, basic and organic solvents. There is a mutually beneficial relationship between MoS₂, C-dots and Fe₃O₄ particles. Magnetic carbon dots (Fe₃O₄@C-dots) prevent MoS₂ layers from agglomerating, while the chemically very stable MoS₂ layers act as a protective layer on magnetic carbon dots. In addition, the –OH and –COOH functional groups of the C-dots lead to improvements in the extraction efficiency of the adsorbent due to the formation of a hydrogen bond between these groups and ibuprofen. Hence, the MoS₂@Fe₃O₄@C-dot NFs as sorbents for the MSPE procedure showed good extraction performance. The new MoS₂@Fe₃O₄@C-dot NFs were used as magnetic solid-phase extraction (MSPE) adsorbents for the separation and enrichment of ibuprofen from pharmaceutical, environmental water and synthetic urine samples before high pressure liquid chromatography (HPLC-DAD) determination. MoS₂@Fe₃O₄@C-dot NFs were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), Raman spectroscopy and SEM-mapping techniques. The optimization of analytically important variables such as pH, adsorbent amount, eluent type and volume, sample volume and extraction time was performed. In the experiments performed, the recoveries of ibuprofen from pharmaceutical, environmental water and synthetic urine samples were in the range of 89–105%. The limit of detection (LOD), limit of quantification (LOQ) and preconcentration factor (PF) were found to be 11 × 10⁻⁶ μg mL⁻¹, 34 × 10⁻⁶ μg mL⁻¹ and 100, respectively. The relative standard deviation values within the day (intra-day) and between days (inter-day) were calculated to be 1.29% and 3.19%, respectively.

中文翻译：

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石墨烯样的MoS2修饰的磁性C点纳米花：一种有效的磁性固相萃取吸附剂，用于监测痕量的布洛芬

像石墨烯一样的二维过渡金属_二硫化氢，例如MoS ₂，MoSe ₂，MoTe ₂，NbS ₂，NbSe ₂，WS ₂，WSe ₂，TaS ₂和TaSe ₂，由于它们的基本特性而正在出现。在实际应用中对石墨烯进行补充。在这项研究中，石墨烯状的MoS ₂修饰的磁性碳点纳米花（MOS ₂ @Fe ₃ ö ₄ @ C-点NFS）合成通过一个简单而绿色的水热合成方法。碳点（C点）是通过非常简单的一步水热合成方法从牛奶中获得的。由于MoS ₂的夹心层提供了足够和有效的中间层空间，因此大量的磁性碳点可以轻松进入这些层之间的这些空间。MoS ₂水溶液在酸性，碱性和有机溶剂中具有良好的化学稳定性和分散性。MoS ₂，C点和Fe ₃ O ₄颗粒之间存在互利关系。磁性碳点（Fe ₃ O ₄ @C点）可防止MoS ₂化学上非常稳定的MoS ₂层充当磁性碳点上的保护层。另外，由于这些点与布洛芬之间形成氢键，C点的–OH和–COOH官能团可提高吸附剂的萃取效率。因此，作为MSPE程序吸附剂的MoS ₂ @Fe ₃ O ₄ @C点NFs表现出良好的萃取性能。新的MoS ₂ @Fe ₃ O ₄在高压液相色谱（HPLC-DAD）测定之前，将@ C-点NFs用作磁性固相萃取（MSPE）吸附剂，用于从药品，环境水和合成尿液样品中分离和富集布洛芬。MoS ₂ @Fe ₃ O ₄使用X射线衍射（XRD），场发射扫描电子显微镜（FE-SEM），拉曼光谱和SEM映射技术对@C点NFs进行了表征。对重要的分析变量进行了优化，例如pH，吸附剂数量，洗脱液类型和体积，样品体积和提取时间。在进行的实验中，从药品，环境水和合成尿液样品中布洛芬的回收率在89％至105％之间。检出限（LOD）的极限，定量限（LOQ）和富集因数（PF）的极限被认为是11×10 ^-6微克毫升^-1，34×10 ^-6微克毫升^-1和100。计算一天中（一天之内）和一天之间（一天之内）的相对标准偏差值分别为1.29％和3.19％。