Quantitative Method Development for Organic Environmental Compounds Automating Isotope Dilution Mass Spectrometry

Defense Date

12-8-2006

Graduation Date

Spring 1-1-2007

Availability

Restricted

Submission Type

dissertation

Degree Name

PhD

Department

Chemistry and Biochemistry

Committee Chair

H. M. Skip Kingston

Committee Member

Bruce D. Beaver

Committee Member

Kasi Somayajula

Committee Member

Mitchell E. Johnson

Keywords

Environmental Analysis, Gas Chromatography, Isotope Dilution, Mass Spectrometry, Quantitative analysis, Solid Phase Extraction, SPE

Abstract

For decades, sample preparation has been a bottleneck for analyses, despite innovations in analytical instrumentation. A primary goal of this research is to address such drawbacks. Quantitation is performed using stable isotope analogs, as internal standards, or as isotope dilution standards. The focus of this research is the development and application of novel extraction techniques for the following three areas; small, polar analytes hard to extract from aqueous matrices (e.g. MTBE, etc.), matrices that create problems during sample extraction (samples with high % moisture, organic biomass, etc.), novel improvements over traditional methods of sample preparation. The dissertation is categorized into seven chapters. Chapter 1 introduces basic theoretical concepts of extraction and presents a survey of different extraction techniques. Chapter 2 discusses analysis and quantitation with relevant theory as it applies to the experimental data. Three quantitation methods, external standard, internal standard, and isotope dilution, have been discussed and compared. Chapter 3 initiates the experimental section, starting with SPE. The theory is discussed extensively, followed by the presentation of experimental data for compounds like MTBE, dioxane, benzene, toluene ethylbenzene and xylenes (collectively known as BTEX). A bioremediation study is described and illustrated. Chapter 4 introduces a new concept, Presorbed Stable Isotope-Solid Phase Extraction (PSI-SPE). The success is demonstrated through the analysis of both laboratory-prepared and real world samples. Chapter 5 introduces another novel concept, Microwave Assisted Test Tube Extraction (MATTE), which, as proposed, is a very rapid and efficient method to determine which sites need further investigation showing promise to be an effective sample screening tool. Chapter 6 focuses on high-moisture soils and sediment and the modifications that these types of samples entail. One such modification resulted in the development of Microwave Assisted Solid Phase Extraction (MASPE). This research develops methodology that is more effective than traditional extraction and internal standard protocols. Demonstration of improvements in these protocols provides enhanced accuracy, precision, efficiency, and cost effective environmental monitoring.

Format

PDF

Language

English

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