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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. v ACKNOWLEDGEMENTS I would like to give my sincere thanks to Dr. Joseph J. Pesek for being my research advisor and providing me an opportunity to work on this project. I am grateful for his valuable feedback during the course of the research work. I truly appreciate his guidance in writing my thesis and his insightful comments in evaluating my thesis. I am also grateful to Dr. Maria Matyska Pesek for teaching me new instruments and techniques during the period of my research. I would like to take this opportunity to thank my committee members, Dr. Roger Terrill and Dr. Patrick E. Fleming, for helping me from time to time during my research work and for evaluating my thesis. I cannot thank enough to the chemistry department team members: Mr. Michael Stephens, the lead technician, and Mr. Craig Wood, the equipment technician, for providing me with their assistance for the lab instruments. Finally, I am heartily thankful to my husband, Vipool Prajapati, for his endless support and understanding throughout my research work. I am deeply thankful to my little warriors, Rushil Prajapati (5) and Samarth Prajapati (2), for providing me all their mommy-and-me time to finish up my research work and thesis. I am immensely grateful to our parents for their encouragement and support in focusing towards the goals of my research. vi TABLE OF CONTENTS LIST OF FIGURES ………………………………………………………………….....ix LIST OF TABLES ………………………………………………………………….....xiv I. INTRODUCTION ………………………………………………………………...1 A. Chromatography …………………………………………………………..1 B. High Performance Liquid Chromatography (HPLC).