title: Fabrication of ZIF-8@SiO2 core-shell microspheres as the stationary phase for high-performance liquid chromatography.
abstract: 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.
authors: 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.
authors: Yan-Yan
authors: YY
authors: Fu
authors: Cheng-Xiong
authors: CX
authors: Yang
authors: Xiu-Ping
authors: XP
authors: Yan
keywords: core-shell microspheres; liquid chromatography; metal-organic frameworks; stationary phases; zeolites