Abstract3D magnetic hollow porous CdFe2O4 microspheres (3D MHPS-CdFe2O4) were prepared by a one-step and template-free hydrothermal method. The material was applied for magnetic solid phase extraction of three azo colorants (Acid Red, Congo Red, Sunset Yellow). Compared to conventional CdFe2O4 nanoparticles, the new 3D material exhibits superior extraction capability because of its unique hollow porous structure, high specific surface area, and the strong interaction between 3D microspheres and the colorants. A magnetic solid phase extraction (MPSE) combined with HPLC was established for simultaneous detection of the three azo colorants in food samples. Under optimum conditions, the detection limits are 0.54–1.00 ng mL-1, and good recoveries of 87.0–100.7% were obtained with spiked samples, with relative standard deviation of ≤ 3.8%. The combination of using the new 3D material and MPSE-HPLC results in an efficient, sensitive and inexpensive method for simultaneous determination of such colorants. Graphical abstractSchematic of the preparation of 3D magnetic hollow porous CdFe2O4 microspheres as solid phase extractant for simultaneous trace detection of three azo colorants in real samples.

中文翻译：

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3D 空心多孔 CdFe2O4 微球作为磁性固相萃取偶氮着色剂的可行材料

摘要 采用一步法、无模板水热法制备了三维磁性空心多孔CdFe2O4微球(3D MHPS-CdFe2O4)。该材料用于三种偶氮着色剂（酸性红、刚果红、日落黄）的磁性固相萃取。与传统的 CdFe2O4 纳米粒子相比，这种新型 3D 材料具有独特的中空多孔结构、高比表面积以及 3D 微球与着色剂之间的强相互作用，因此具有卓越的提取能力。建立了磁固相萃取（MPSE）结合高效液相色谱法同时检测食品样品中三种偶氮染料的方法。在最佳条件下，检出限为 0.54–1.00 ng mL-1，加标样品获得了 87.0–100.7% 的良好回收率，相对标准偏差≤ 3.8%。使用新的 3D 材料和 MPSE-HPLC 的组合产生了一种高效、灵敏且廉价的方法来同时测定此类着色剂。图解摘要制备 3D 磁性空心多孔 CdFe2O4 微球作为固相萃取剂用于同时检测实际样品中三种偶氮着色剂的示意图。