Direct probing of chromatography columns by laser-induced fluorescence

Abstract

This report summarizes the progress and accomplishments of this research project from September 1, 1989 to February 28, 1993. During this period, we have accomplished ali of the primary scientific objectives of the research proposal: 1) constructed and evaluated a laser-induced fluorescence detection system that allows direct examination of the chromatographic column, 2) examined nonequilibrium processes that occur upon solute injection and elution, 3) examined solute retention in liquid chromatography as a function of temperature and pressure, 4) examined solute zone dispersion in liquid chromatography as a function of temperature and pressure, and 5) developed appropriate theoretical models to describe these phenomena. In each of these studies, substantial knowledge has been gained of the fundamental processes that are responsible for chromatographic separations. lr, addition to these primary research objectives, we have made significant progress in three related areas: 1) examined pyrene as a fluorescent polarity probe in supercritical fluids and liquids as a function of temperature and pressure, 2) developed methods for the class-selective identification of polynuclear aromatic hydrocarbons in coal-derived fluids by microcolumn liquid chromatography with fluorescence quenching detection, and 3) developed methods for the determination of saturated and unsaturated (including omega-3) fatty acids in fish oil extracts by microcolumn liquid chromatography with laser-induced fluorescence detection. In these studies, the advanced separation and detection techniques developed in our laboratory are applied to practical problems of environmental and biomedical significance.