Separation of Chiral Enantiomers in LC Enantioseparations

In a recent review article published in the Journal of Chromatography A, a team of researchers provided an overview of the strides made in the separation of chiral enantiomers of drugs (1).

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To understand how liquid chromatography (LC) enantioseparations became a hot topic in research circles, the authors discussed how back in 1991, the US Food and Drug Administration (FDA) released the first guidelines for the development of chiral drugs. These guidelines set the stage for research and technological advancements aimed at distinguishing between mirror-image molecules that exhibit identical physical and chemical properties but behave differently in biological systems (1).

Since then, the field of chromatographic enantioseparation tools has made significant strides, evolving rapidly to create an optimal environment for the separation of chiral enantiomers (1). The article highlights two major avenues of research that have been instrumental in this endeavor: the immobilization of chiral selectors (CS) on diverse stationary phases, and the utilization of chiral mobile phase additives (CMPA) (1).

The immobilization of CS on various stationary phases has emerged as a potent approach to enantioseparation (1). This technique involves grafting chiral selectors onto a solid matrix, thereby creating a selective environment that favors the binding of one enantiomer over the other. The authors discuss how comprehensive examination of the different recognition mechanisms drive this separation process, which helps explain the interplay between the enantiomers and the chiral selectors (1).

Chromatographers have also been exploring the potential of chiral mobile phase additives (CMPA) as a cost-effective alternative to traditional chiral stationary phases. When incorporated into the mobile phase of a chromatographic system, these additives induce selective interactions between the analytes and the stationary phase, enabling successful enantioseparation (1). The article underscores the considerable progress made in this area, showcasing how CMPAs have evolved to achieve impressive separation results (1).

As the pharmaceutical industry continues to evolve, the separation of chiral enantiomers remains a critical aspect of drug development. The insights presented in this review article will be used by researchers to help them develop more effective and efficient methods of chiral enantiomer separation, paving the way for safer and more targeted pharmaceutical products (1).

Reference

(1) Ibrahim, A. E.; El Gohary, N. A.; Aboushady, D.; et al. Recent advances in chiral selectors immobilization and chiral mobile phase additives in liquid chromatographic enantioseparations: A review. J. Chromatogr. A. 2023, 1706, 464214. DOI: 10.1016/j.chroma.2023.464214