Recent developments in liquid and supercritical-fluid chromatographic enantioseparations

This chapter highlights the latest trends and developments in performing enantioseparations in various modes of liquid chromatography (LC) and in sub/supercritical fluid chromatography (SFC). Existing and newly introduced selectors are discussed along with their chiral recognition mechanism, with a major focus on those selectors that are incorporated in commercially available chiral stationary phases (CSP). Applications included from the last 5 years show more than a conventional chiral separation of some compounds. Polysaccharide-based CSPs undoubtedly remain the most used in performing chiral separations in LC and SFC, as they display the broadest enantiorecognition range. Other frequently used selectors are macrocyclic antibiotics and ion exchangers, along with Pirkle-type selectors and cyclodextrins. New selectors such as zwitterionic ion exchangers and cyclofructans are extending the current range of selectors. Clearly, emphasis in the field of chiral separations has evolved more towards ultrafast and efficient separations, which is reflected in the development of CSP that use superficially porous and sub-2 μm particles. Such stationary phases allow the achievement of subminute, and even subsecond, separations.