Vibrational Spectroscopy of Chromatographic Interfaces

Abstract

Structure-Function Studies in RPLC Stationary PhasesChromatographic separations play a central role in DOE-supported fundamental research related to energy, biological systems, the environment, and nuclear science. The overall portfolio of research activities in the Separations and Analysis Program within the DOE Office of Basic Energy Sciences includes support for activities designed to develop a molecular-level understanding of the chemical processes that underlie separations for both large-scale and analytical-scale purposes. The research effort funded by this grant award was a continuation of DOE-supported research to develop vibrational spectroscopic methods to characterize the interfacial details of separations processes at a molecular level. A. Raman Spectroscopy of Alkylsilane-Based RPLC Stationary Phase MaterialsStudies of stationary and mobile phase structure in this laboratory seek a unified molecular picture of stationary phase-stationary phase, solute-stationary phase, solute-mobile phase solvent, stationary phase-mobile phase solvent, and mobile phase solvent-solvent interactions that dictate retention in reversed phase liquid chromatography (RPLC.) In order to utilize Raman spectroscopy for elucidation of structural parameters for RPLC stationary phases (SPs) that are relevant to retention mechanism, model systems must be identified and validated in terms of spectral indicators of the structural attribute that one wishes to understand. Toward this end, by analogy with our earlier work in identifying Raman