The Use of Dual Cyclodextrin Chiral Selector Systems in the Enantioseparation of Pharmaceuticals by Capillary Electrophoresis: An Overview

Abstract

Cyclodextrin (CD) derivatives are the most efficient and frequently used chiral selectors (CSs) in capillary electrophoresis (CE). There are situations when the use of a single CD as CS is not enough to obtain efficient chiral discrimination of the enantiomers; in these cases, sometimes this problem can be resolved using a dual CD system. The use of dual CD systems can often dramatically enhance enantioseparation selectivity and can be applied for the separation of many analytes of pharmaceutical interest for which enantioseparation by CE with another CS systems can be problematic. Usually in a dual CD system an anionic CD is used together with a neutral one, but there are situations when the use of a cationic CD with a neutral one or the use of two neutral CDs or even two ionized CDs can be an efficient solution. In the current review we present general aspects of the use of dual CD systems in the analysis of pharmaceutical substances. Several examples of applications of the use of dual CD systems in the analysis of pharmaceuticals are selected and discussed. Theoretical aspects regarding the separation of enantiomers through simultaneous interaction with the two CSs are also explained. Finally, advantages, disadvantages, potential and new direction in this chiral analysis field are highlighted.

Sensitivity enhancement in capillary electrophoresis and their applications for analyses of pharmaceutical and related biochemical substances

“…CE is a useful method for drug discovery and development in various aspects (e.g., determinations of active ingredients, counterions, and impurities [138,139], enantiomeric separation [139][140][141][142][143][144][145][146], screenings of pK a , and determination of log p values [147][148][149], etc.). Challenges in producing sensitive and reliable quantitative data depend on the instrumentation setup, sample pretreatment/preconcentration, and hyphenated with suitable detectors.…”

Comparative studies on enantioseparation of New Psychoactive Substances using cyclodextrin-assisted capillary electrophoresis with UV detection

“…Capillary electrophoresis (CE) counts as a complementary technique to HPLC and represents a powerful alternative for separation of enantiomers by means of simple method development and low sample and electrolyte consumption combined with inexpensive UV detection. In this field, previous work has already shown the potential of cyclodextrins as chiral additives in CE [19][20][21]. This chiral selector class comprises 6 (α-), 7 (β-) or 8 (γ-cyclodextrin) cyclic glycopyranose units forming a truncated cone.…”

Capillary Electrophoresis Mass Spectrometry: Developments and Applications for Enantioselective Analysis from 2011–2020

“…Apart from the aforementioned enantioselective interactions, the solute's adsorption to the column walls must be considered to understand the analyte retention behavior. For more recent details on the enantioselective mechanisms in CE, several excellent reviews are available [10,11].…”