FTIR and Raman Characteristic Peak Frequencies in Biological Studies - Vibrational Spectroscopy for Tissue Analysis - page 278

Table 8.1 ( Continued )
Major Characteristic Peak Frequencies Reported in the Literature

Reference
Number Peak Assignment FT-IR Raman

1680 cm −1 Unordered random coils and

turns of amide I

* 83

νC= O * 1

1681 cm −1 C= O guanine deformation N-H

in plane

* 48

* 1

νC= O

1682 cm −1 One of the absorption positions

for the C= O stretching
vibrations of cortisone

* 102

C= O * 1

1684 cm −1 C= O guanine deformation N-H

in plane

* 48

1685 cm −1 Amide I (disordered structure;

nonhydrogen bonded)

* * 7

1690 cm −1 Peak of nucleic acids due to the

base carbonyl stretching and
ring breathing mode

* 50

1694 cm −1 A high-frequency vibration of an

antiparallel β-sheet of amide I

* 83

(The amide I band is due to
in-plane stretching of the C= O
band weakly coupled with
stretching of the C-N and
in-plane bending of the N-H
bond.)

1695 cm −1 νC= O * 1

1697 cm −1 Amide I (turns and bands) * 43

1698/9 cm −1 C 2 = O guanine * 48

N-H thymine * 48

1700-15 cm −1 The region of the bases * 23

1700-50 cm −1 ν(C= O)OH (amino acids aspartic

and glutamic acid)

* 7

1700-800 cm −1 Fatty acid esters * 56

Lipids observed during cell
apoptosis (more specifically at
1740 cm −1 )

* 39

1700/2 cm −1 C= O guanine * 48

1702 cm −1 C= O thymine * 48

Stretching C= O vibrations that
are H-bonded. (Changes in the
C= O stretching vibrations could
be connected with destruction of
old H-bonds and creation of the
new ones.)

* 48