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Abstract

Although silica-based columns are still the most frequent in HPLC analyses, the sorbents based on metal oxides have already found their place in liquid chromatography. Compared to silica gel, the zirconia and Titania phases differ in temperature and pH stability as well as in retention mechanism. In our previous study we found that compounds with the Lewis acid character are significantly retained in both low and high content of organic component in the mobile phase. This behavior suggests that the Lewis base-Lewis acid interactions play an important role in the retention process on the zirconium surface. These are also responsible for broader peaks on HPLC in compare with silica phases. The possibilities of using ZrO 2 sorbents in a selective extraction of analytes were designed on the basis of these previously obtained results. Mainly the interactions between acidic model compounds and bare zirconia or zirconia modified with ion exchangers were studied under various aqueous rich (different pH, buffer) or HILIC (98% ACN) conditions. It was tried to separate the analytes from plasma and tablet matrix or concentrate some NSAID from large volume water sample on the SPE columns filled with zirconia sorbents.

Biography

Klivicky M gained his Master degree in pharmacy from Charles University in Prague, Faculty of Pharmacy in Hradec Králové and he currently attend a PhD programme Pharmaceutical Analysis on the Department of Pharmaceutical Chemistry and Drug Analysis. Stationary phases based on metal oxides are the main topic of his research.