9318484 Hawkridge This award is made in the Analytical and Surface Chemistry Program in support of the research of Dr. Sarah Rutan. The research is aimed at elucidating the role of the solvated stationary phase in reversed phase liquid chromatography. This will be achieved through the use of indicators whose UV-visible absorbance maxima are dependent on their molecular environments. Solvatochromic parameters describing the dipolarity/polarizability, hydrogen bond acidity and hydrogen bond basicity will be determined. Spectra of various indicators in mixed aqueous/organic supensions of stationary phase particles which have been derivatized with alkyl chains will be obtained using diffuse reflectance spectroscopy. Interferences from dye molecules that remain in the bulk mobile phase will be eliminated using adaptive filtering techniques. In a related study, factor analysis methods will be used to aid in the development of methods for the prediction of infinite dilution activity coefficients and heats of solution, based on these solvatochromic parameters. The combination of improved modeling techniques and the development of parameters describing the chemistry of the chromatographic phases should ultimately allow the researcher to predict retention characteristics for solutes in reversed phase liquid chromatography. This capability will be of significant benefit across a broad range of industrial and medically related separations and may also prove valuable to the characterization of other interfacial systems.
