Investigation on performance of zirconia and magnesia–zirconia stationary phases in hydrophilic interaction chromatography

Preparation, chromatographic evaluation and application of adenosine 5′-monophosphate modified ZrO2/SiO2 stationary phase in hydrophilic interaction chromatography

“…As reported in our previous study [26], the bare ZrO 2 column was demonstrated to be unsuitable for separating acids in HILIC mode, possibly owing to excessively strong adsorption between acids and Lewis acid sites on the surface of ZrO 2 . However, for 5 -AMP-ZrO 2 /SiO 2 SP, Lewis acid sites were occupied by the 5 -AMP molecules, which may offer appropriate retention for acidic compounds.…”

“…For comparison, the bare ZrO 2 (prepared according to our previous report [26]) and ZrO 2 /SiO 2 were also separately pumped into the columns of the same dimension.…”

“…The buffered MP could improve the peak shape, enhance the separation efficiency and ensure the reproducibility [26,30] in HILIC. NH 4 Ac was widely used due to its relatively good solubility in organic solvents and superior compatibility with mass spectrometry.…”

“…Additionally, the bare ZrO 2 monolith [24] and ZrO 2 /SiO 2 composite monolith [25] were attempted in HILIC mode, which had the capacity to differentiate compounds with different spatial configurations. In our recent study [26], the ZrO 2 -based SP was demonstrated as a promising HILIC SP after systematic investigation on the chromatographic performance and retention mechanism of bare ZrO 2 and MgO-ZrO 2 columns.…”

Polar silica‐based stationary phases. Part I ‐ Singly and doubly layered sorbents consisting of TRIS‐silica and chondroitin sulfate A‐TRIS‐silica for hydrophilic interaction liquid chromatography

“…Therefore, polar functional groups are usually bonded onto the bare silica particles or silica monoliths as monomeric or polymeric phases in order to overcome these drawbacks as well as to increase the hydrophilicity of the separation surface, thus broadening the application range of HILIC. Other than silica‐based stationary phases (whether particles or monoliths), organic monoliths and metal oxide based stationary phases have also been developed for HILIC separations. A wide variety of functional groups including amide, cyano, diol, amines, sulfobetaine have been grafted onto the various available supports to produce HILIC stationary phases that can be categorized into four major groups namely, neutral, cationic, anionic and zwitterionic based on the surface charge of the stationary phases, see recent reviews .…”