There is a need for chiral stationary phases (CSPs) designed for high performance liquid chromatography (HPLC) to switch to enantioselective applications using ultrahigh-performance liquid chromatography (UHPLC). Although important goals have been achieved to rapidly separate achiral compounds, enantioselective LC remains solidly attached to 3-μm and 5-μm totally porous particles and pressure values in the HPLC domain. This article describes strategies aimed at immobilizing or coating well-established chiral selectors onto sub-2-μm silica particles, and aims to illustrate the potential of enantioselective UHPLC (eUHPLC) in terms of high speed, throughput and resolution.
However, enantioselective LC is still performed on 3- and 5-μm totally porous particles, yielding pressure values in the high performance liquid chromatography (HPLC) domain. In fact, although HPLC and UHPLC C18 columns for reversed-phase separations have been extensively discussed and evaluated in literature in terms of kinetic and thermodynamic phenomena, little is known on the efficiency of enantioselective columns. Up to now, the main concern of both users and manufacturers has been a qualitative one: Analyses on a 45-min timescale or longer are considered typical in chiral separations. Is it really not possible to overcome this limitation?