Structural Characterization of Liquid-Chromatographic Effluents via Reverse File-Searching of Fluorescence Spectra

254 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 1980.The work described here has shown the feasibility of combining the technique of liquid chromatography, fluorescence detection and computerized file-searching to produce a new approach to mixture analysis. The technique operates by separating mixture components in a liquid-chromatograph and submitting them sequentially to a high-performance spectrofluorometer for spectral characterization. The excitation and emission fluorescence spectra are searched against a library containing more than 1150 compounds, by a new algorithm which compares spectral similarity from the point of view of both the unknown spectrum and the library spectrum, thus combining the best features of forward and reverse searching.Implementation of this approach has involved the development of both hardware and software. Hardware requirements have included the construction of liquid chromatograph and spectrofluorometer, as well as electronic interfaces for computer control of the instrument. Software requirements have included design of the new file-searching algorithm and development of programs for instrument control, data acquisition and reduction as well as various display and library maintenance functions.The capabilities of the completed system have been explored by examination of several different types of mixtures. Polycyclic aromatic hydrocarbons have been shown to be particularly amenable to analysis by this method, at low concentration levels and in various combinations. Completely automated analysis of these mixtures has been achieved. The detection of quinine directly from tonic water shows the ability of the method to deal with samples without elaborate extraction or other sample preparation. Several pharmaceutical applications have shown the system's performance on samples containing very few spectral features. The ability to give qualitative information on mixtures of biological interest was shown with a study of rat urine.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD