Terahertz Circular Dichroism Spectroscopy of Biopolymers
Abstract
We are developing a terahertz circular dichroism (TCD) spectrometer to explore functionally relevant terahertz vibrational modes of biopolymers. CD, the differential absorption of opposite circularly polarized radiation, can only occur in the presence of chiral media. Since biopolymers are net chiral, with some caveats, CD senses biological modes, uncontaminated by non-biological features. TCD allows in vitro THz spectroscopy of biopolymers in strongly absorbing non-biological media. Heretofore, THz CD has not been explored. Theory predicts weak but rich TCD spectra. THz absorption corresponds to dynamic modes that can soften into large-scale conformational changes necessary to carry out life functions. We have developed a TCD spectrometer by driving a polarizing interferometer with the UCSB FELs (0.12 - 5 THz). We measure, for the first time, TCD due to lysozyme in water, and discuss the utility for biochemical sensing.
- Publication:
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APS March Meeting Abstracts
- Pub Date:
- March 2004
- Bibcode:
- 2004APS..MARH14007X