RATIONALE Sedatives, which are prone to cause residues in animals, have been abused in modern animal husbandry. Long-term consumption of contaminated meat products would be unfavorable to the human nervous system. Taking into account public health and food safety, it was essential to develop an effective method for the enrichment and detection of sedatives in meat. METHODS Fe3 O4 @TbBd@ZIF-8 composites were synthesized by using Fe3 O4 nanoparticles as a magnetic core and 1,3,5-triformylbenzene (Tb) and benzidine (Bd) as two building blocks to form Fe3 O4 @TbBd. Furthermore, the zeolitic imidazolate framework-8 (ZIF-8) was modified on the surface of the Fe3 O4 @TbBd. In addition, Fe3 O4 @TbBd@ZIF-8 was used as a magnetic solid-phase extraction (MSPE) adsorbent of typical animal sedatives in pork samples. Mass spectrometry analysis was conducted by electrospray ionization triple-quadrupole mass spectrometry in positive-ion multiple reaction monitoring mode. RESULTS By combining the optimized MSPE approach with high-performance liquid chromatography/tandem mass spectrometry (HPLC/MS/MS), an accurate and sensitive method for the determination of sedatives was developed. The method exhibited good linearity in the range of 0.03-70 μg/kg with the correlation coefficient (R2 ) ranging from 0.9982 to 0.9999, high sensitivity with limits of detection (LODs) ranging from 0.04 to 0.2 μg/kg, and high precision with relative standard deviation (RSD) less than 5.5%. The adsorption behaviors of Fe3 O4 @TbBd@ZIF-8 towards sedatives were more suitably described by a pseudo-second-order kinetic and Freundlich isotherm model. CONCLUSIONS The proposed MSPE-HPLC/MS/MS method was successfully applied to the determination of sedatives in real samples and showed excellent applicability. Several sedatives were detected in the selected meat samples. The developed method was shown to be facile, sensitive and accurate for sedative detection and also showed great prospects for determination of sedatives from other complex samples.

中文翻译：

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轻松制备磁性共价有机骨架-金属有机骨架复合材料，作为有效的吸附剂，可通过高效液相色谱/串联质谱法测定肉类样品中的镇静剂。

RATIONALE镇静剂很容易在动物体内引起残留，在现代畜牧业中已被滥用。长期食用受污染的肉类产品将不利于人类神经系统。考虑到公共卫生和食品安全，必须开发一种有效的方法来丰富和检测肉类中的镇静剂。方法以纳米Fe3O4为磁性核，以1,3,5-三甲酰苯（Tb）和联苯胺（Bd）为两个结构单元，合成Fe3O4 @ TbBd @ ZIF-8复合材料，形成Fe3O4 @ TbBd。此外，在Fe3O4 @ TbBd的表面上改性了沸石咪唑盐骨架8（ZIF-8）。另外，Fe3O4 @ TbBd @ ZIF-8用作猪肉样品中典型动物镇静剂的磁性固相萃取（MSPE）吸附剂。质谱分析是通过电喷雾电离三重四极杆质谱在正离子多反应监测模式下进行的。结果通过将优化的MSPE方法与高效液相色谱/串联质谱法（HPLC / MS / MS）相结合，开发了一种准确而灵敏的镇静剂测定方法。该方法在0.03-70μg/ kg的范围内表现出良好的线性，相关系数（R2）在0.9982至0.9999之间，灵敏度高，检测限（LOD）在0.04至0.2μg/ kg范围内，并且在相对标准偏差（RSD）小于5.5％。Fe3 O4 @ TbBd @ ZIF-8对镇静剂的吸附行为更适合用拟二级动力学和Freundlich等温模型描述。结论所提出的MSPE-HPLC / MS / MS方法已成功应用于实际样品中镇静剂的测定，并显示出极好的适用性。在选定的肉类样品中检测到了几种镇静剂。所开发的方法被证明是简便，灵敏且准确的镇静剂检测方法，也显示了从其他复杂样品中测定镇静剂的广阔前景。