Preconcentration and separation solutions for simultaneous determination
of complex panels of analytes in pharmaceutical and clinical applications

Tomasz Bączek, Department of Pharmaceutical Chemistry, Medical University of Gdańsk, Hallera 107, 80-416 Gdańsk, Poland, tomasz.baczek@gumed.edu.pl

Very often the efficient use of liquid chromatography coupled to mass spectrometry (LC-MS) capillary zone electrophoresis (CZE), like micellar electrokinetic chromatography (MEKC) or microemulsion electrokinetic chromatography (MEEKC)-based separation methods could not be sufficient without carrying out proper off-line sample preparation procedure and the choice of the most efficient on-line preconcentration technique for investigated compounds. To improve concentration detection limits, off-line sample preparation techniques, like liquid-liquid extraction (LLE), liquid-liquid microextraction (LLME), dispersive liquid-liquid microextraction (DLLME), solid-phase extraction (SPE) or solid-phase microextraction (SPME) are some of commonly applied techniques. Among on-line preconcentration methods there are relevant approaches allowing the quantification of trace amounts of compounds in pharmaceutical and biomedical samples. In here, the field-amplified sample stacking (FASS) [known also as field-enhanced sample stacking (FESS)], field-amplified sample injection (FASI) [known also as field-enhanced sample injection (FESI)] are the best recognized ones. Sweeping, micelle to solvent stacking (MSS), p-ITP (pseudo-isotachophoresis) or FESI in conjunction with sweeping (sequential stacking featuring sweeping, SSFS) are another analyte enrichment techniques. In parallel, one should remember also about the possibilities to optimize CE methods playing with hydrodynamic injection (HDI), electrokinetic injection (EKI), simultaneous EKI and HDI (SEHI) or repetitive injection (RI). Several examples of novel approaches based on variable combinations of mentioned techniques and methods to be applied for the analysis of mixtures of selected drug and endogenous substances, like e.g., LC-MS, SPME-LC-MS/MS, MEKC, SPE-MEKC, RI-FASS-CZE, DLLME-FASS-MEKC, DLLME-FASI-p-ITP, LLE-MSS-CZE, SPME-SEHI-SSFS-MEKC or ionic liquid-assisted SPME-MEKC and 3D-printed-assisted SPME-MEKC, are going to be thoroughly presented and discussed.

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Abstract Reference & Short Personal Biography of Presenting Author

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