This review focuses on the use of superficially porous particles (SPPs) as chiral stationary phases for ultra-high performance liquid enantioseparations. In contrast to what happened in achiral separations where core-shell particles invaded the market, the introduction of SPPs in chiral liquid chromatography (LC) has been relatively recent. This is due in part to the technical difficulties in the preparation of these phases, and in part to scarce understanding of mass transfer phenomena in chiral chromatography. As a matter of fact, nowadays, the development of superficially porous CSPs is still in its infancy. This paper covers the most recent advancements in the field of core-shell technology applied to chiral separations. We review the kinds of chiral selectors that have been used for the preparation of these phases, by discussing the advantages of chiral SPPs over their fully-porous counterparts for high efficient high throughput enantioseparations. Notwithstanding the apparently obvious advantages in terms of the mass transfer of chiral SPPs, some critical aspects that could impact their development are presented.

With the aim of pushing forward the limits of high efficient and ultrafast chiral liquid chromatography, a new Chiral Stationary Phase (CSP) has been prepared by covalently bonding the teicoplanin selector on 2.0μm Superficially Porous Particles (SPPs). An already validated bonding protocol, which permits to achieve teicoplanin-based CSPs exhibiting zwitterionic behaviour, has been employed to prepare not only the 2.0μm version of the CSP but also two other analogous CSPs based, respectively, on 2.7μm SPPs and 1.9μm Fully Porous Particles (FPPs). The kinetic performance of these CSPs has been compared through the analysis of both van Deemter curves and kinetic plots by employing in-house packed columns of 4.6mm internal diameter and different lengths (20, 50 and 100mm). In particular on the columns packed with 2.0μm SPPs, extremely large efficiencies were observed for both achiral (>310,000 theoretical plates/meter, N/m; h: 1.61) and chiral compounds (>290,000 N/m; h: 1.72) in HILIC conditions. Thanks to their efficiency and enantioselectivity, these CSPs were successfully employed in ultrafast chiral separations. As an example, the enantiomers of haloxyfop were baseline resolved in about 3s, with a resolution higher than 2.0, (flow rate: 8mL/min) on a 2cm long column packed with the 2.0μm chiral SPPs.

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Liquid chromatography coupled to low-resolution mass spectrometry (LRMS) has historically been a popular approach for compound quantitation. Recently, high-resolution mass spectrometry (HRMS) technical developments led to the introduction of new approaches for quantitative analysis. Whereas the performances of HRMS have been largely assessed for qualitative purposes, there are still questions about its suitability for quantitative analysis. Several papers on LRMS and HRMS comparison have been published; however, none of them was applied to polyphenol quantitation. In this work, a comparison between HRMS, operated in data-dependent acquisition mode, and LRMS, operated in selected-reaction-monitoring mode, was performed for polyphenol quantitation in wine. The two techniques were evaluated in terms of sensitivity, linearity range, matrix effect, and precision, showing the better performances of HRMS. The suitability of HRMS for quantitation purposes as well as qualitative screening makes HRMS the new technique of choice for both targeted and untargeted analysis.