Master of Science (MS)
Joseph J. Pesek
Aqueous Normal Phase Chromatography, Carbohydrates, Amino acids, Organic acids, Fluorinated Stationary Phases, HPLC-ELSD
Chemistry, Analytical; Chemistry, General; Chemistry, Organic
Silica-based fluorinated bonded stationary phases have shown enhanced selectivity with altered elution orders for molecules differing in hydrophobicity and hydrophilicity in comparison with C8 and C18 reversed phase columns. Hence, two novel silica hydride-based fluorinated bonded phases have been synthesized using a hydrosilation
procedure to exploit fluorine-based unique selectivity for polar basic metabolites. Bonded moieties have been characterized by elemental and spectral analyses. Silica hydride-based aqueous normal phase (ANP) chromatography has retention behavior similar to normal phase chromatography, except for the use of water as a part of the binary solvent (>60 % acetonitrile : water). In ANP, a higher percentile of nonpolar mobile phase shows increased retention for acids and bases, and nonpolar solutes can also be retained as in reversed phase chromatography (RPC). The synergistic effects of fluorinated phases' altered selectivity and aqueous normal phase retentivity have been
explored for small polar metabolites using high performance liquid chromatography (HPLC) coupled with several detectors. Hydride-based fluorinated stationary phases showed good stability and remarkable reproducibility in retention time with %RSD < 1.
Prajapati, Kavita Vipool, "Synthesis and Evaluation of Silica Hydride-Based Fluorinated Stationary Phases" (2010). Master's Theses. 3785.