ANYL 232 |
| The use of Raman spectroscopy to determine structure-function relationships in long chain alkylsilane stationary phases for reversed-phase liquid chromatography (RPLC) is presented. Raman spectroscopy is used to determine conformational order for a series of high-density docosylsilane (C22) stationary phases that vary in surface coverage from 3.61 to 6.97 umol/m2 as a function of various chromatographic parameters. The effect of these parameters on the conformational order of the alkylsilanes conveys detailed information about molecular interactions at the chromatographic interface that provide insight into mechanisms of solute retention in RPLC. Spectral data are correlated with chromatographic behavior for a series of simple aromatic compounds in three methanol-water mobile phases on one stationary phase of surface coverage 4.89 umol/m2 to gain insight into retention mechanism. Specifically, a spectral indicator of conformational order can be correlated with octanol-water partitioning coefficient for these compounds. Results suggest that while solute partitioning into the C22 stationary phase occurs, it is restricted to the distal ends of the alkylsilanes. |
|
Honoring Mary Wirth, Recipient of the Spectrochemical Analysis Award
1:30 PM-5:00 PM, Tuesday, 12 September 2006 Moscone Center -- Room 123, Oral
Division of Analytical Chemistry |