State Key Laboratory of Medicinal Chemical Biology (Nankai University), Synergetic Innovation Center of Chemical Science and Engineering (Tianjin) and Research Center for Analytical Sciences, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071 (P. R. China), Fax: (86) 22-23506075.
Chemistry. 2013 Sep 27;19(40):13484-91. doi: 10.1002/chem.201301461. Epub 2013 Aug 16.
The unique features of high porosity, shape selectivity, and multiple active sites make metal-organic frameworks (MOFs) promising as novel stationary phases for high-performance liquid chromatography (HPLC). However, the wide particle size distribution and irregular shape of conventional MOFs lead to lower column efficiency of such MOF-packed columns. Herein, the fabrication of monodisperse MOF@SiO2 core-shell microspheres as the stationary phase for HPLC to overcome the above-mentioned problems is reported. Zeolitic imidazolate framework 8 (ZIF-8) was used as an example of MOFs due to its permanent porosity, uniform pore size, and exceptional chemical stability. Unique carboxyl-modified silica spheres were used as the support to grow the ZIF-8 shell. The fabricated monodisperse ZIF-8@SiO2 packed columns (5 cm long × 4.6 mm i.d.) show high column efficiency (23,000 plates m(-1) for bisphenol A) for the HPLC separation of endocrine-disrupting chemicals (bisphenol A, β-estradiol, and p-(tert-octyl)phenol) and pesticides (thiamethoxam, hexaflumuron, chlorantraniliprole, and pymetrozine) within 7 min with good relative standard deviations for 11 replicate separations of the analytes (0.01-0.39, 0.65-1.7, 0.70-1.3, and 0.17-0.91% for retention time, peak area, peak height, and half peak width, respectively). The ZIF-8@SiO2 microspheres combine the advantages of the good column packing properties of the uniform monodisperse silica microspheres and the separation ability of the ZIF-8 crystals.
具有高孔隙率、形状选择性和多个活性位点等独特特性的金属有机骨架（MOFs）有望成为高效液相色谱（HPLC）的新型固定相。然而，传统 MOFs 的粒径分布较宽且形状不规则，导致此类 MOF 填充柱的柱效较低。在此，报道了将单分散 MOF@SiO2核壳微球用作 HPLC 的固定相，以克服上述问题。由于沸石咪唑酯骨架 8（ZIF-8）具有永久孔隙率、均匀的孔径和卓越的化学稳定性，因此被用作 MOFs 的示例。独特的羧基改性硅球被用作支撑物来生长 ZIF-8 壳。所制备的单分散 ZIF-8@SiO2 填充柱（5 cm 长×4.6 mm id）在 7 min 内对内分泌干扰物（双酚 A、β-雌二醇和对叔辛基苯酚）和农药（噻虫嗪、六氟脲、氯虫苯甲酰胺和吡虫啉）的 HPLC 分离表现出高柱效（双酚 A 为 23,000 板 m-1），11 次重复分析物分离的相对标准偏差良好（保留时间、峰面积、峰高和半峰宽分别为 0.01-0.39、0.65-1.7、0.70-1.3 和 0.17-0.91%）。ZIF-8@SiO2 微球结合了均匀单分散硅微球良好的柱填充性能和 ZIF-8 晶体的分离能力的优势。
