2005 APS March Meeting
Monday–Friday, March 21–25, 2005;
Los Angeles, CA
Session N5: Applications of THz Radiation
8:00 AM–11:00 AM,
Wednesday, March 23, 2005
LACC
Room: 502B
Sponsoring
Unit:
FIAP
Chair: Alan Todd, Advanced Energy Systems and Gwyn P. Williams, Jefferson Lab
Abstract ID: BAPS.2005.MAR.N5.2
Abstract: N5.00002 : Submillimeter wave spectroscopy of biological macromolecules
8:36 AM–9:12 AM
Preview Abstract
Abstract
Author:
Tatiana Globus
(University of Virginia)
The recently emergence of submillimeter-wave or terahertz (THz)
spectroscopy
of biological molecules has demonstrated the capability to detect
low-frequency internal molecular vibrations involving the weakest
hydrogen
bonds of the DNA base pairs and/or non-bonded interactions. These
multiple
bonds, although having only $\sim $ 5{\%} of the strength of
covalent bonds,
stabilize the structure of bio-polymers, by holding the two
strands of the
DNA double helix together, or polypeptides together in different
secondary
structure conformations. There will be a review of THz-frequency
transmission (absorption) results for biological materials
obtained from
Fourier Transform Infrared (FTIR) spectroscopy during the last
few
years$^{1,2}$. Multiple resonances, due to low frequency
vibrational modes
within biological macromolecules, have been unambiguously
demonstrated in
qualitative agreement with theoretical prediction, thereby
confirming the
fundamental physical nature of observed resonance features. The
discovery of
resonance character of interaction between THz radiation and
biological
materials opens many possible applications for THz spectroscopy
technique in
biological sensing and biomedicine using multiple resonances as
distinctive
spectral fingerprints. However, many issues still require
investigation.
Kinetics of interactions with radiation at THz has not been
studied and
vibrational lifetimes have not been measured directly as a
function of
frequency. The strength of resonant modes of bio-molecules in
aqueous
environment and strong dependence of spectra on molecular
orientation need
explanation. Vibrational modes have not been assigned to specific
motions
within molecules. THz spectroscopy of bio-polymers makes it only
in first
steps.
1. T. Globus, D. Woolard, M. Bykhovskaia, B. Gelmont, L. Werbos,
A. Samuels.
International Journal
of High Speed Electronics and Systems (IJHSES), \textbf{13}, No.
4, 903-936
(2003).
2. T. Globus, T. Khromova, D. Woolard and B. Gelmont. Proceedings
of SPIE
Vol. 5268-2, 10-18 (2004)
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2005.MAR.N5.2