Abstract Covalent organic frameworks (COFs) show excellent property, such as high porosity and excellent structure stability and were well applied in fields such as catalysis and adsorption, but most of the COFs showed similar structure and thus similar adsorption performance. Modification of simple COFs to enhance its adsorption performance in separation technique is an important issue. In this study, quaternary ammonium groups with long hydrophobic chain were introduced into a simple COF (TpPa-1) for the first time. The positively charged COF (PC-TpPa-1) can form electrostatic interaction and hydrophobic effect with negatively charged analytes, and showed good adsorption performance for ultraviolet-filters (UV filters). Under the optimum conditions, i.e. adsorbent amount 20 mg, pH = 7, 1.0 mL acetonitrile as eluent, the obtained recoveries for all UV filters were in the range of 86.4–96.7%.The developed method was successfully applied to the determination of UV filters from food packaging material migrants with the aid of HPLC as a detector. Graphical Abstract

中文翻译：

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带正电荷的共价有机骨架及其在食品包装材料迁移物中紫外线滤光剂的分散固相萃取中的应用

摘要 共价有机骨架（COFs）具有孔隙率高、结构稳定性好等优异性能，在催化和吸附等领域得到了很好的应用，但大多数COFs表现出相似的结构，因此具有相似的吸附性能。对简单的 COF 进行改性以提高其在分离技术中的吸附性能是一个重要的问题。在这项研究中，具有长疏水链的季铵基团首次被引入到简单的 COF (TpPa-1) 中。带正电的COF（PC-TpPa-1）可以与带负电的分析物形成静电相互作用和疏水作用，对紫外线过滤器（UV过滤器）表现出良好的吸附性能。在最佳条件下，即吸附剂量为20 mg，pH=7，1.0 mL乙腈为洗脱液，所有紫外线过滤剂的回收率都在 86.4-96.7% 的范围内。该方法成功应用于以 HPLC 为检测器的食品包装材料迁移物中紫外线过滤剂的测定。图形概要