MIL-53-based homochiral metal-organic framework as a stationary phase for open-tubular capillary electrochromatography

Homochiral metal-organic frameworks (MOFs) have attracted considerable attention in many fields of research, such as chiral catalysis and chiral chromatography. However, only few homochiral MOFs can be effectively used in capillary electrochromatography (CEC) and their performances are far from adequate. In this study, we successfully synthesized achiral nanocrystalline MIL-53. A facile post-synthetic modi-fication strategy was then implemented to functionalize the product, yielding a homochiral MOF: L-His-NH-MIL-53. This MOF was then employed as a chiral coating in open-tubular CEC mode (OT-CEC), and, as such, it exhibited high enantioselectivities for several racemic drugs. The homochiral MOF and the fabricated capillary coating were systematically characterized using transmission electron microscopy, scanning electron microscopy (with energy-dispersive X-ray spectrometry), Fourier-transform infrared spectroscopy, X-ray diffractometry, thermogravimetric analysis, circular dichroism spectroscopy, Bru-nauer-Emmett-Teller surface area measurements, and X-ray photoelectron spectroscopy. This study is expected to provide a new strategy for the design and establishment of MOF-based chiral OT-CEC systems. (C) 2021 The Authors. Published by Elsevier B.V. on behalf of Xi'an Jiaotong University.

Automated summary

In this study, a homochiral metal-organic framework (MOF) was successfully synthesized and used as a chiral coating in capillary electrochromatography (CEC), demonstrating high enantioselectivity. The MOF and the fabricated capillary coating were characterized using various techniques, providing insights for the design and establishment of MOF-based chiral CEC systems.