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THE GLOW DISCHARGE - a MULTIFACETED OPTICAL EMISSION SOURCE: from SOLIDS ANALYSIS to METALLOPROTEINS Timothy Brewer Clemson University, [email protected]

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THE GLOW DISCHARGE - a MULTIFACETED OPTICAL EMISSION SOURCE: from SOLIDS ANALYSIS to METALLOPROTEINS Timothy Brewer Clemson University, Tbrewer@Clemson.Edu Clemson University TigerPrints All Dissertations Dissertations 5-2007 THE GLOW DISCHARGE - A MULTIFACETED OPTICAL EMISSION SOURCE: FROM SOLIDS ANALYSIS TO METALLOPROTEINS Timothy Brewer Clemson University, [email protected] Follow this and additional works at: https://tigerprints.clemson.edu/all_dissertations Part of the Analytical Chemistry Commons Recommended Citation Brewer, Timothy, "THE GLOW DISCHARGE - A MULTIFACETED OPTICAL EMISSION SOURCE: FROM SOLIDS ANALYSIS TO METALLOPROTEINS" (2007). All Dissertations. 62. https://tigerprints.clemson.edu/all_dissertations/62 This Dissertation is brought to you for free and open access by the Dissertations at TigerPrints. It has been accepted for inclusion in All Dissertations by an authorized administrator of TigerPrints. For more information, please contact [email protected]. THE GLOW DISCHARGE - A MULTIFACETED OPTICAL EMISSION SOURCE: FROM SOLIDS ANALYSIS TO METALLOPROTEINS _____________________________________________ A Dissertation Presented to the Graduate School of Clemson University _____________________________________________ In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Chemistry _____________________________________________ by Tim M. Brewer May 2007 _____________________________________________ Accepted by: Dr. R. Kenneth Marcus, Committee Chair Dr. Kenneth Christensen Dr. Stephen Creager Dr. Julia Brumaghim ABSTRACT Glow discharges (GD) are well known for their application to direct solids elemental analysis of metals and alloys by optical emission spectroscopy (GD-OES). The most successful application of GD-OES has been the analysis of solid materials since the GD provides rapid, direct bulk and depth profiling analysis of solids, metals, powders, polymers, glasses and ceramics. However, solids analysis has typically suffered from the lack of true analytical blanks and the inability to study particulate solids in their native state. An approach for the analysis of solid powdered material entrapped in a sol-gel matrix by radio frequency glow discharge optical emission spectroscopy (rf-GD-OES) is described. Using the sol-gel method, analytical blanks were obtained by the use of an undoped sol-gel. Through sol-gel chemistry, entrapment of solid powdered material (i.e., Portland cement and oligonucleotides) in a solid glass matrix is achieved. Slurries of powdered materials were incorporated into the films and analyzed for both metallic and non-metallic elemental components. Rf- GD-OES is capable of easily determining non-metals due to the inert atmosphere. Cast films are analyzed to determine the optimum discharge operating conditions and effects of particle size as well as deposited layer thickness. iii Even though depth profiling of solid layered surfaces and thin films has been the major area of application for GDs, recent trends have focused on the analysis of liquid solutions for elemental species studies. The coupling of particle beam sample introduction and hollow cathode optical emission spectroscopy (PB/HC-OES) was applied for empirical formula determinations of a group of nucleotides. The phosphorous and carbon atomic emission from ribonucleotide compounds was monitored and the analyte element response (P (I) and C (I)) to the glow discharge operation conditions was studied. To further demonstrate the capability of the PB/HC-OES as a liquid chromatography detector for biomolecules, iron containing metalloproteins were separated and determined by PB/HC-OES through monitoring of iron atomic emission. Reversed phase high performance liquid chromatography was used to separate and isolate an iron-protein mixture followed by PB/HC-OES iron specific detection. Parametric optimization for sample introduction, nebulization and hollow cathode source conditions were performed for the analysis of iron-containing metalloproteins. iv DEDICATION This work is dedicated to my parents Marty and Janet Brewer and to my entire family, who support and encourage me through all that I do and have done, and especially to my wife Becky, who makes it all worthwhile and brings such a joy into my life. v vi ACKNOWLEDGEMENTS First I would like to thank my research advisor Dr. R. Kenneth Marcus, for his guidance and the opportunities that he gave me as a graduate student. I want to thank him for the opportunity to explore a wide range of projects and for encouraging me to follow some of my own ideas in the later part of my tenure. Additionally, the opportunity he gave me to present at national conferences and the interactions with other professionals from academia and industry have greatly influenced my professional development. The time I have spent working for him has been one second to none and will value forever. Assistance from Paula Cable-Dunlap at Savannah River National Laboratory and the Clemson University Department of Chemistry for instrumentation and financial support is greatly appreciated. I would like to express my sincere thanks to Paula R. Cable-Dunlap and W. Clay Davis for research collaboration opportunities throughout the past few years as well as leadership and mentoring. Without Paula Cable-Dunlap’s help my time as a graduate student would not have been possible. I would also like the present and past member of the Marcus group, which has made my graduate experience all the more enjoyable. First and foremost, I would like to thank my mentor, W. Clay Davis. His guidance and support provided a solid background throughout the development of my graduate research career. The friendship and helpful advice of vii Rayman Stanelle has played an important part throughout my graduate school tenure. Most of all, I want to express my sincere appreciation to my family and friends, who have stood strong throughout my seemingly endless education. I am truly blessed for their continuing love, support, and understanding throughout my education at Clemson University. I would like to thank Bill Medler, who gave me the courage to pursue a degree in chemistry. viii TABLE OF CONTENTS Page TITLE PAGE...................................................................................... i ABSTRACT ....................................................................................... iii DEDICATION .................................................................................... v ACKNOWLEDGEMENTS.................................................................. vii LIST OF TABLES .............................................................................. xv LIST OF FIGURES ............................................................................ xix CHAPTER 1. INTRODUCTION ......................................................................... 1 Glow Discharge........................................................................ 1 Glow Discharge Devices .......................................................... 1 Spatial Regions of Glow Discharge Plasma......................... 5 Cathodic Sputtering.............................................................. 10 Excitation and Ionization ...................................................... 12 Hollow Cathode Discharge................................................... 18 Radio Frequency Operating Modes ..................................... 21 Liquid Sample Analysis by Hollow Cathode Glow Discharge .......................................................................... 24 Transport Type Liquid Chromatography-Mass Spectrometry Interfaces .................................................... 26 Particle Beam Transport Type Interface............................... 28 Liquid Chromatography Coupling and Speciation Analysis ........................................................... 31 Summary.................................................................................. 33 ix Table of Contents (Continued) Page 2. PLASMA PARAMTER AND FILM CASTING OPTIMIZATION FOR THE DETERMINATION OF PARTICULATE MATTER IN A SOL-GEL MATRIX BY RADIOFREQUENCY GLOW DISCHARGE OPTICAL EMISSION SPECTROMETRY (RF-GD-OES)............................................ 35 Introduction .............................................................................. 35 Experimental ............................................................................ 39 Sol-gel Film Preparation....................................................... 39 Instrumentation .................................................................... 41 Results and Discussion............................................................ 43 Optimization of Discharge Operation Parameters........................................................................ 43 Sputter Analysis and Analyte Emission Responses for Sol-gels ..................................................... 46 Effect of Particle Size on Emission Characteristics .................................................................. 53 Effect of Cast-Film Thickness on Emission Characteristics .................................................................. 57 Analytical Figures of Merit.................................................... 60 Conclusions.............................................................................. 64 Acknowledgements .................................................................. 65 3. NON-METAL ELEMENTAL DETECTION BY RADIO-FREQUENCY GLOW DISCHARGE OPTICAL-EMISSION SPECTROMETRY (RF-GD-OES) FOR DETERMINATION OF SOL-GEL IMMOBILIZED NUCLEOTIDES............................... 67 Introduction .............................................................................
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