ANYL 146 |
| It is well-known that bile salts such as cholic acid and deoxycholic acid can be effectively used to form a pseudostationary phase in micellar electrokinetic capillary chromatography (MEKC) and employed for separating chiral isomers of molecules that have fairly planar molecular geometry. Although there have been numerous reports of bile salts as the basis for chiral separations in both chromatography and capillary electrophoresis, the molecular-level interactions between the isomers and the micelles is not well characterized. Even the exact mechanisms of formation for the micelle from surfactant monomers are not well understood. This work attempts to infer such information through careful and systematic characterization of both the MEKC behavior of model-drug analytes and nuclear magnetic resonance (NMR) signals obtained from the MEKC solutions. Using the model analytes 1,1'-binaphthyl-2,2'diyl hydrogenphosphate and 1,1'-binaphthyl as probes, we are able to closely examine the interactions between micelle and chiral isomers and have begun to understand how the micelle and analytes interact. We also have further examined the interactions of bile salt monomers as they form micelles. The NMR examination of these aqueous MEKC systems has included 1H and 31P chemical shift analysis as well as relaxation time experiments, and these data are correlated with MEKC results. We will present recent results from both MEKC and NMR that aid our increasing understanding of the complicated set of interactions between individual bile salt monomers, bile salt micelles and the analyte molecules. |
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General Papers
7:00 PM-9:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Division of Analytical Chemistry |