posted on 2021-12-21, 16:11authored byGioacchino Luca Losacco, Heather Wang, Imad A. Haidar Ahmad, Jimmy DaSilva, Alexey A. Makarov, Ian Mangion, Francesco Gasparrini, Michael Lämmerhofer, Daniel W. Armstrong, Erik L. Regalado
Enantioselective
chromatography has been the preferred technique
for the determination of enantiomeric excess across academia and industry.
Although sequential multicolumn enantioselective supercritical fluid
chromatography screenings are widespread, access to automated ultra-high-performance
liquid chromatography (UHPLC) platforms using state-of-the-art small
particle size chiral stationary phases (CSPs) is an underdeveloped
area. Herein, we introduce a multicolumn UHPLC screening workflow
capable of combining 14 columns (packed with sub-2 μm fully
porous and sub-3 μm superficially porous particles) with nine
mobile phase eluent choices. This automated setup operates under a
vast selection of reversed-phase liquid chromatography, hydrophilic
interaction liquid chromatography, polar-organic mode, and polar-ionic
mode conditions with minimal manual intervention and high success
rate. Examples of highly efficient enantioseparations are illustrated
from the integration of chiral screening conditions and computer-assisted
modeling. Furthermore, we describe the nuances of in silico method development for chiral separations via second-degree
polynomial regression fit using LC simulator (ACD/Labs) software.
The retention models were found to be very accurate for chiral resolution
of single and multicomponent mixtures of enantiomeric species across
different types of CSPs, with differences between experimental and
simulated retention times of less than 0.5%. Finally, we illustrate
how this approach lays the foundation for a streamlined development
of ultrafast enantioseparations applied to high-throughput enantiopurity
analysis and its use in the second dimension of two-dimensional liquid
chromatography experiments.