17 Vibrational Microspectroscopy for Analysis of Atherosclerotic Arteries
527
the most important spectral features of atherosclerotic plaque are given in
table 17.2.
Functional Investigation and Classification of Atherosclerotic Plaque
the very first mapping experiment concerning atherosclerotic tissue was done as
early as in 1991 by Kodali et al. [54]. A point microscope with small throughput
was used, therefore the results are limited to fragments of the aorta. An image of the
whole cross-section was also done, but with a very large step giving a very general
overview of the tissue, which yet is a nice achievement with not imaging-dedicated
equipment. that work laid foundations for later research, identifying major tissue
components and corresponding bands as discussed in 5.2.2.1.
the next imaging work done on a synchrotron [54] was focused on differentiation between collagen types (I and III) and elastin, which are the main components
of aortic wall and fibrous cap covering the lesion. the authors managed to successTable 17.2 the most prominent bands present in atherosclerotic plaque of infrared spectra with
their mode and corresponding compound assignment [67, 127].
Wavenumber [cm
−1
] mode assignment
Compound assignment
1041
C-o stretching
oligosaccharides and polysaccharides
1055
Cholesterol
1080–1095
Po 2
−
symmetric stretching, C-o
stretching
Phospholipids and nucleic acids glycogen, oligosaccharides and glycolipids,
calcification
1151
C-o stretching
glycogen and nucleic acids
1170
Co-o-C asymmetric stretching
of ester group
Cholesteryl esters
1203
Collagen
1239
Po 2
−
asymmetric stretching
Phospholipids and nucleic acids
1395–1377
Ch 2 bending
Lipids and proteins (amide III)
1460
Ch 2 scissoring
Lipids
1552
C = o, Nh,
Proteins (amide II)
1666
C = o, Nh,
Proteins (amide I)
1733–1750
C = o stretching of ester group Lipids and triglycerides
(C = o stretching of ester group)
2850
Ch 2 symmetric stretching
Lipids
2873
Ch 3 symmetric stretching
Proteins mainly
2925
Ch 2 asymmetric stretching
Lipids
2954
Ch 3 asymmetric stretching
Lipids
3008
= Ch stretching
oleic and linoleic acid moiety
3035
olefinic ring breathing
Cholesterol
3080
oh, Nh
Proteins (amide B)
3500–3200
oh, Nh
Proteins (amide A), sugars, calcification
527
the most important spectral features of atherosclerotic plaque are given in
table 17.2.
Functional Investigation and Classification of Atherosclerotic Plaque
the very first mapping experiment concerning atherosclerotic tissue was done as
early as in 1991 by Kodali et al. [54]. A point microscope with small throughput
was used, therefore the results are limited to fragments of the aorta. An image of the
whole cross-section was also done, but with a very large step giving a very general
overview of the tissue, which yet is a nice achievement with not imaging-dedicated
equipment. that work laid foundations for later research, identifying major tissue
components and corresponding bands as discussed in 5.2.2.1.
the next imaging work done on a synchrotron [54] was focused on differentiation between collagen types (I and III) and elastin, which are the main components
of aortic wall and fibrous cap covering the lesion. the authors managed to successTable 17.2 the most prominent bands present in atherosclerotic plaque of infrared spectra with
their mode and corresponding compound assignment [67, 127].
Wavenumber [cm
−1
] mode assignment
Compound assignment
1041
C-o stretching
oligosaccharides and polysaccharides
1055
Cholesterol
1080–1095
Po 2
−
symmetric stretching, C-o
stretching
Phospholipids and nucleic acids glycogen, oligosaccharides and glycolipids,
calcification
1151
C-o stretching
glycogen and nucleic acids
1170
Co-o-C asymmetric stretching
of ester group
Cholesteryl esters
1203
Collagen
1239
Po 2
−
asymmetric stretching
Phospholipids and nucleic acids
1395–1377
Ch 2 bending
Lipids and proteins (amide III)
1460
Ch 2 scissoring
Lipids
1552
C = o, Nh,
Proteins (amide II)
1666
C = o, Nh,
Proteins (amide I)
1733–1750
C = o stretching of ester group Lipids and triglycerides
(C = o stretching of ester group)
2850
Ch 2 symmetric stretching
Lipids
2873
Ch 3 symmetric stretching
Proteins mainly
2925
Ch 2 asymmetric stretching
Lipids
2954
Ch 3 asymmetric stretching
Lipids
3008
= Ch stretching
oleic and linoleic acid moiety
3035
olefinic ring breathing
Cholesterol
3080
oh, Nh
Proteins (amide B)
3500–3200
oh, Nh
Proteins (amide A), sugars, calcification