Open Access Dissertation
Date of Award
Colin F. Poole
Despite the wide application of solid-phase extraction (SPE) in the environmental, clinical and pharmaceutical fields, method development for this technique has remained largely an empirical process of trial and error. In an effort to provide a systematic approach to method development, the kinetic and retention properties of four popular siloxane-bonded SPE sorbents have been determined. Kinetic measurements allow the evaluation of the performance of extraction devices and reveal areas in which small changes in design or manufacture could improve sampling characteristics. Application of the solvation parameter model to retention data yields a set of system constants that describe the ability of the solvated stationary phase to compete with the bulk mobile phase for specific, clearly defined, intermolecular interactions with the solute. Once established, system constants can be used for the prediction of retention for any compound for which solute descriptors are available, the identification of new sorbents with sampling properties that set them apart from materials already available, and the prediction of breakthrough volume in SPE. Knowledge of breakthrough volume is a key parameter for predicting extraction conditions which are likely to be successful, thus eliminating a large portion of the guesswork involved in method development.
Seibert, Donna S., "The characterization of silica-based sorbents in reversed phase liquid chromatography with application to method development in solid-phase extraction" (1998). Wayne State University Dissertations. 1231.