Biological Sensing with Terahertz Circular Dichroism Spectroscopy

Abstract

We have developed a circular dichroism spectrometer working in the terahertz (THz) frequency regime. As THz spectroscopy is specific to collective vibrational modes in macromolecules (and collective modes in condensed, polar media such as water), the spectrometer should provide spectral fingerprints of biological materials. Moreover, by focusing on circular dichroism the spectrometer should provide fingerprints of these materials uncontaminated by the strong background absorbance of water and other polar materials. We have built this spectrometer and have pushed its signal to noise down to 1 part in 10^4. While this is more than sufficient to detect the strong circular dichroism of macroscopic, chiral objects, it is apparently insufficient to observe circular dichroism arising from common biological materials. Current efforts are aimed at 1-2 orders of magnitude improvements on this detection limit.

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Document Details

Document Type
Technical Report
Publication Date
May 31, 2005
Accession Number
ADA440274

Entities

People

  • Kevin W Plaxco
  • S. J. Allen

Organizations

  • University of California, Santa Barbara

Tags

Communities of Interest

  • Human Systems

DTIC Thesaurus Topics

  • Absorption
  • Absorption Coefficients
  • Absorption Spectra
  • Abstracts
  • Albumins
  • Biomolecules
  • Detection
  • Far Infrared Lasers
  • Femtosecond Time
  • Free Electron Lasers
  • Materials
  • Measurement
  • Optical Properties
  • Spectroscopy
  • Standing Waves
  • Students
  • Terahertz Radiation

Fields of Study

  • Physics

Readers

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