PMID- 16925918
OWN - NLM
STAT- MEDLINE
DCOM- 20070516
LR  - 20060823
IS  - 0003-7028 (Print)
IS  - 0003-7028 (Linking)
VI  - 60
IP  - 8
DP  - 2006 Aug
TI  - Orientation-insensitive spectra for Raman microspectroscopy.
PG  - 841-6
AB  - Separating effects due to molecular conformation from those due to orientation in 
      the spectra of oriented samples obtained by Raman microspectroscopy is a complex 
      issue. To solve this problem, we propose a procedure to calculate an 
      orientation-insensitive spectrum (so-called isotropic spectrum) from polarized 
      spectra obtained by Raman microspectroscopy that is valid for systems that 
      exhibit a uniaxial symmetry. The method has first been tested on highly oriented 
      samples of high-density polyethylene (HDPE). Polarized and isotropic spectra of a 
      highly oriented HDPE cylindrical rod and an isotropic HDPE sample have been 
      compared. The differences in the relative intensities, which occur in the 
      polarized spectra and are due to orientation of the polyethylene chains, are 
      nearly cancelled in the isotropic spectra, showing that the 
      orientation-insensitive spectrum adequately represents the molecular conformation 
      without contributions of orientation. Second, spectra of silk fibroins have been 
      compared in the amide I region for Bombyx mori cocoon silk fibers and 
      methanol-treated regenerated fibroin films. The similarity of the shape of the 
      amide I band of the isotropic spectra indicates that the secondary structure of 
      the fibroins is very close in both samples. These experimental results support 
      the conclusion that the molecular conformation can be efficiently characterized 
      from the intensity and the shape of Raman bands in the orientation-insensitive 
      spectrum.
FAU - Lefevre, Thierry
AU  - Lefevre T
AD  - Centre de Recherche en Sciences et Ingenierie des Macromolecules, Centre de 
      Recherche sur la Fonction, la Structure et l'Ingenierie des Proteines, 
      Departement de Chimie, Universite Laval, Pavillon Alexandre-Vachon, Quebec 
      (Quebec), Canada G1K 7P4.
FAU - Rousseau, Marie-Eve
AU  - Rousseau ME
FAU - Pezolet, Michel
AU  - Pezolet M
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Appl Spectrosc
JT  - Applied spectroscopy
JID - 0372406
RN  - 0 (Silk)
RN  - 9002-88-4 (Polyethylene)
SB  - IM
MH  - Animals
MH  - Bombyx
MH  - Models, Theoretical
MH  - Polyethylene/*chemistry
MH  - Protein Structure, Secondary
MH  - Silk/*chemistry
MH  - Spectrum Analysis, Raman/*methods
EDAT- 2006/08/24 09:00
MHDA- 2007/05/17 09:00
CRDT- 2006/08/24 09:00
PHST- 2006/08/24 09:00 [pubmed]
PHST- 2007/05/17 09:00 [medline]
PHST- 2006/08/24 09:00 [entrez]
AID - 10.1366/000370206778062039 [doi]
PST - ppublish
SO  - Appl Spectrosc. 2006 Aug;60(8):841-6. doi: 10.1366/000370206778062039.