Chiral metal–organic frameworks (MOFs) have aroused great attention in the chiral separation field based on their excellent characteristics, including abundant topological structures, large surface area, adjustable pore/channel sizes, multiple active sites, and good chemical stability. However, the irregular morphology and nonuniformity of the synthesized MOF particles cause low column efficiency and high column backpressure for MOF-packed columns, which significantly affects their separation performance. Herein, we prepared a homochiral d-his-ZIF-8@SiO2 composite by growing of d-his-ZIF-8 on the carboxylic-functionalized SiO2 microspheres via a simple one-pot synthesis approach. The d-his-ZIF-8@SiO2 core–shell microspheres with uniform particles and narrow size distribution were applied as the chiral stationary phase (CSP) for enantioseparations in HPLC. Various racemates were separated on the d-his-ZIF-8@SiO2-packed columns with n-hexane/isopropanol as the mobile phase. Eighteen racemates including alcohol, phenol, amine, ketone, and organic acid were well resolved on the homochiral d-his-ZIF-8@SiO2 CSP. The d-his-ZIF-8@SiO2 core–shell microspheres’ CSP possesses an excellent chiral resolution ability toward various racemic compounds with good reproducibility and stability. Hence, the fabrication of chiral MOF@SiO2 core–shell microspheres is an effective strategy to improve the application of homochiral MOFs as CSPs in the field of chromatography.

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The unique features of uniform and adjustable cavities, abundant chiral active sites, and high enantioselectivity make chiral metal‐organic frameworks popular as an emerging candidate for enantioselective separation. However, the wide particle size distribution and irregular shape of as‐synthesized metal–organic frameworks result in low column efficiency, undesired chromatographic peak shape, and high column backpressure of such metal–organic frameworks packed columns. Herein, we report the fabrication of chiral core‐shell microspheres [Cu2(d‐Cam)2(4,4′‐bpy)]n@SiO2 composite for high‐performance liquid chromatography enantioseparation to overcome the above‐mentioned problems. The [Cu2(d‐Cam)2(4,4′‐bpy)]n@SiO2 packed column gave high‐resolution separation of racemates under low column backpressure (10‐22 bar), indicating its synergistic effect of the good column packing property of the SiO2 microspheres and the chiral recognition ability of [Cu2(d‐Cam)2(4,4′‐bpy)]n crystals. Thirteen kinds of chiral compounds including alcohols, amines, ketones, epoxides, and organic bases were well separated with good peak shapes and high column efficiency (18200 plates/m for 1‐(9‐anthryl)‐2,2,2‐trifluoroethanol) on the [Cu2(d‐Cam)2(4,4′‐bpy)]n@SiO2 packed column. Among them, seven pairs of enantiomers achieved baseline separation and the resolution value for 1‐(9‐anthryl)‐2,2,2‐trifluoroethanol reached 11.22. Some effects such as column temperature, and analytes mass on the enantioseparations have been investigated. In addition, the [Cu2(d‐Cam)2(4,4′‐bpy)]n@SiO2 packed column exhibited good stability and repeatability for the separation of chiral compounds. The relative standard deviations for five replicate separations of 1‐phenylethanol were less than 1.0, 1.5, 3.0, and 2.0% for the retention time, peak area, number of theoretical plates, and resolution, respectively. The research results demonstrated the development of chiral metal–organic frameworks core‐shell microspheres composite provide a promising platform for their practical application in chiral separation fields.

A highly sensitive luminescence sensor based on PLNPs for visualized detection of antibiotic and organic explosives was developed, which could eliminate the background interference, allowing low background and therefore high sensitivity.