ANYL 32 |
| Frequency doubling (second harmonic generation, SHG) and frequency mixing (sum frequency generation, SFG) are remarkably sensitive to molecular and macromolecular chirality. Whereas absorbance measurements yield circular dichroic (CD) ratios of a few fractions of a percent, these same molecular systems can easily produce CD ratios approaching 100% in SHG and SFG measurements of thin films. Our recent efforts have focused on development of an experimental and theoretical toolbox to assist in transitioning these emerging techniques to practical biological characterization. Experimentally, novel ellipsometric approaches for polarization analysis improve information content and reduce acquisition times. As a complement, new and relatively simple theories have been proposed and tested for interpreting the relationships between the detected signals and the molecular/macromolecular structures at the interfaces. Applications of these combined experimental and theoretical techniques include the demonstration of label-free methods for real-time biosensing, chiral-specific detection and analysis with ultra-high sensitivity, and zero-background real-time detection of biomolecule crystallization. |
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Analytical Division Award Symposium
1:30 PM-5:05 PM, Sunday, August 19, 2007 BCEC -- 104C, Oral
Division of Analytical Chemistry |