CAS Key Laboratory of Chemistry of Northwestern Plant Resources and Key Laboratory for Natural Medicine of Gansu Province, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, Lanzhou 730000, China.
Analyst. 2020 Jun 2;145(11):3851-3856. doi: 10.1039/d0an00304b.
A new type of core-shell composite material was prepared and applied as a hydrophilic interaction liquid chromatography (HILIC) stationary phase. In this work, silica spheres were first modified with a bimetallic central metal-organic framework (ZnCoMOF) by a new strategy of static self-assembled in situ growth. This strategy was beneficial for increasing the electrostatic interaction between the MOF ligand and silica via introducing a sodium dodecylbenzenesulfonate (SDBS) group. The ZnCoMOF@silica stationary phase was characterized and evaluated in comparison with amino-modified and bare silica columns in terms of various polar analytes including eight nucleosides and nucleobases, seven carbohydrates, and multiple sulfonamides and antibiotics. The effects of organic solvent concentration, water content, the concentration of the salt and the pH of the buffer solution on the retention time were studied, which demonstrated the typical retention behavior of HILIC on the ZnCoMOF@silica column. Compared with most reported MOF-based stationary phases, the new composite material showed excellent hydrophilic properties and separation efficiency for various polar analytes. Moreover, the obtained stationary phase showed good reproducibility and stability. The relative standard deviation (RSD) of the retention time for repeatability was found to range from 0.1% to 0.6%, and the RSD of the retention time for stability was found to range from 0.3% to 0.7%. Furthermore, the column batch-to-batch reproducibility showed excellent preparation reproducibility, which few reported in most previous MOF@silica composite materials. This specific preparation method offers an easy and novel way to manipulate the amount of MOF particles on silica, which extends a universal way to produce various MOF@silica stationary phases by the method of static self-assembled in situ growth.
一种新型核壳复合材料被制备出来，并被应用于亲水相互作用液相色谱（HILIC）固定相。在这项工作中，首先通过一种新的静态自组装原位生长策略，用双金属中心金属有机骨架（ZnCoMOF）对硅胶球进行改性。该策略有利于通过引入十二烷基苯磺酸钠（SDBS）基团增加 MOF 配体与硅胶之间的静电相互作用。通过比较氨基改性和裸硅胶柱，对 ZnCoMOF@silica 固定相进行了表征和评估，以研究包括八种核苷和碱基、七种碳水化合物以及多种磺胺类药物和抗生素在内的各种极性分析物。研究了有机溶剂浓度、水含量、盐浓度和缓冲溶液 pH 值对保留时间的影响，这表明了 ZnCoMOF@silica 柱上 HILIC 的典型保留行为。与大多数报道的基于 MOF 的固定相相比，新型复合材料对各种极性分析物表现出优异的亲水性和分离效率。此外，所得固定相表现出良好的重现性和稳定性。重复性的保留时间相对标准偏差（RSD）范围为 0.1%至 0.6%，稳定性的保留时间 RSD 范围为 0.3%至 0.7%。此外，柱批次间重现性显示出出色的制备重现性，这在大多数以前报道的 MOF@silica 复合材料中很少见。这种特定的制备方法为控制硅胶上 MOF 颗粒的数量提供了一种简单而新颖的方法，通过静态自组装原位生长的方法扩展了生产各种 MOF@silica 固定相的通用方法。
