Chiral hydrogen-bonded organic frameworks used as a chiral stationary phase for chiral separation in gas chromatography

Abstract

Hydrogen-bonded organic frameworks (HOFs) are two dimensional (2D) or three dimensional (3D) porous crystalline materials constructed by Hydrogen bond interaction. In recent years, a variety of functional HOF materials have been successfully synthesized and used in structural identification, environmental pollutant removal, chiral resolution, drug delivery, fluorescence sensing, etc. Here, we first reported that a HOF to coated capillary column for high-resolution gas chromatographic separation of a wide range of analytes, including n-alkanes, n-alcohols, polycyclic aromatic hydrocarbons, and positional isomers, especially for racemates, the HOFs column showed excellent separation repeatability and reproducibility. The relative standard deviation (RSD) values for the retention times were in the range of 0.37-2.43% for run to run (n = 3), 0.38-2.51% for day-to-day (n = 3), and 0.31-2.54% for column-to-column (n = 3), respectively. Moreover, we applied density-functional theory to calculate the adsorption of enantiomers in HOF structures. This work proved that the HOFs had great application prospects as stationary phase in gas chromatography.

Keywords: Capillary column; Chiral separation; Chiral stationary phase; Hydrogen-bonded organic frameworks.