Main areas of research Environmental Chemistry Surface Chemistry Electrochemistry Chromatography Organized Molecular Assemblies Biological Nanostructures Chemical Education

Last Modified: 12:00 PM, Mon Mar 29, 1999

Characterization and Control of Chromatographic Interfaces
Synthesis and Characterization of Novel Organically Modified Sol Gels for use as Chromatographic Stationary Phases

While reverse-phase liquid chromatography is the most widely employed mode of liquid chromatography, the molecular basis for its action is not fully understood. While much research has focused on the chromatographic behavior of carefully chosen solute molecules in an effort to elucidate retention mechanisms, only a few researchers have applied spectroscopic methods to study this question. In this laboratory we are examining real chromatographic stationary phases with normal Raman spectroscopy to develop a molecular picture of the chromatographic interface. The behavior of monomeric and polymeric C18 stationary phases under various chromatographic conditions have been examined. Conditions studied so far include single and binary solvent systems with variations in the dielectric constant and temperature. Each of these parameters affects the relative conformational order of the stationary phase, the parameter we believe is directly correlated with retention behavior.

Characterization of Chromatographic Stationary Phases using Raman Spectroscopy
A Systematic Investigation of Operating Parameters on Stationary Phase Conformation Order

Reverse-phase liquid chromatography (RPLC) is arguably the most common mode of liquid chromatography used. Not just unique to academic research laboratories, RPLC is used by government agencies to prove regulatory compliance, medical laboratories to identify drug metabolites, and industry to monitor quality control. Despite the wide use of RPLC, a fundamental mechanism of separation has yet to be obtained through investigation of stationary phases with chromatography, NMR, fluorescence, and even IR. The ultimate purpose of this research is to elucidate the molecular basis of a mechanism of separation with Raman spectroscopy.