Li Fei, Li Xiaoxuan, Su Jie, Li Yijun, He Xiwen, Chen Langxing, Zhang Yukui
College of Chemistry, Tianjin Key Laboratory of Biosensing and Molecular Recognition, State Key Laboratory of Medicinal Chemical Biology, Nankai University, Tianjin, 300071, China.
School of Chemistry and Chemical Engineering, Shandong University, Jinan, Shandong, 250100, China.
Talanta. 2021 Aug 15;231:122339. doi: 10.1016/j.talanta.2021.122339. Epub 2021 Mar 24.
In this work, a novel strategy to prepare molecularly imprinted polymers (MIPs) functionalized magnetic carbon nanotubes (MCNTs) via a facile sol-gel polymerization by adopting Cu-mediating interaction was presented for selective recognition of celastrol (Cel), in the traditional Chinese medicines (TCM). Firstly, template Cel, 3-aminopropyltriethoxysilane (APTES) as monomer and Cu (co-monomer) were mixed to form a self-assembled pre-complex, in which Cu could coordinate with Cel. Meanwhile, APTES plays a role of bridge between APTES and Cel. Secondly, carboxyl modified MCNTs as substrate was added into the pre-complex solution. After that, a multi-step sol-gel polymerization process was occurred in the presence of tetraethylorthosilicate as cross-linker and acetic acid as catalyst. Finally, MIPs layer was formed on the surface of the MCNTs (Cel-MIPs@MCNTs) after the removal of template with methanol/acetic. The morphology and structure of Cel-MIPs@MCNTs was investigated by various characterization techniques. The adsorption performance of Cel-MIPs@MCNTs to Cel was illustrated by kinetic, isothermal and selective binding experiments. The results displayed that the Cel-MIPs@MCNTs possessed fast kinetic equilibrium time (40 s), high adsorption capacity (13.35 μg mg), good imprinting factor of 3.41, and high magnetic responsivity (44.38 emu·g), which can be used as an ideal adsorbent for rapid isolation and enrichment of target analytes. A selective and sensitive method based on Cel-MIPs@MCNTs coupling with HPLC was developed for Cel determination including a wide linear range (0.15-200 μg mL) with correlation coefficient of 0.9998, a low limit of detection (0.05 μg mL). Furthermore, the applicability of Cel-MIPs@MCNTs was demonstrated to isolate and determine Cel in TCM samples with satisfactory recoveries ranged from 84.47% to 91.5% (RSD<5.35%). The results revealed that Cel-MIPs@MCNTs offer great potential as an adsorbent for selective and efficient isolation of Cel from complex TCM samples.
在本研究中，提出了一种通过采用铜介导相互作用的简便溶胶-凝胶聚合制备功能化磁性碳纳米管（MCNTs）的分子印迹聚合物（MIPs）的新策略，用于选择性识别中药中的雷公藤红素（Cel）。首先，将模板Cel、作为单体的3-氨丙基三乙氧基硅烷（APTES）和铜（共聚单体）混合形成自组装预络合物，其中铜可与Cel配位。同时，APTES在APTES和Cel之间起桥梁作用。其次，将羧基修饰的MCNTs作为底物加入预络合物溶液中。之后，在正硅酸乙酯作为交联剂和乙酸作为催化剂的存在下发生多步溶胶-凝胶聚合过程。最后，用甲醇/乙酸去除模板后，在MCNTs表面形成MIPs层（Cel-MIPs@MCNTs）。通过各种表征技术研究了Cel-MIPs@MCNTs的形貌和结构。通过动力学、等温吸附和选择性结合实验说明了Cel-MIPs@MCNTs对Cel的吸附性能。结果表明，Cel-MIPs@MCNTs具有快速的动力学平衡时间（40秒）、高吸附容量（13.35μg·mg）、良好的印迹因子3.41和高磁响应性（44.38emu·g），可作为快速分离和富集目标分析物的理想吸附剂。建立了一种基于Cel-MIPs@MCNTs与高效液相色谱联用的选择性灵敏方法用于Cel的测定，线性范围宽（0.15-200μg·mL），相关系数为0.9998，检测限低（0.05μg·mL）。此外，证明了Cel-MIPs@MCNTs在分离和测定中药样品中的Cel方面的适用性，回收率令人满意，范围为84.47%至91.5%（相对标准偏差<5.35%）。结果表明，Cel-MIPs@MCNTs作为从复杂中药样品中选择性高效分离Cel的吸附剂具有巨大潜力。
