Table 1.

Raman band frequencies and assignments of Brain Tissue.

Raman shift ${\mathrm{cm}}^{-1}$	Assignmenta	Attribution remarks
676	$\nu$ ($\delta$ (CCN), Vinyl & Porphyrin	CYTc, G of DNA
754	${\mathrm{CH}}_2$ Rock, Sym. breathing	Tryp, mitochondria 2nd peak $747{\mathrm{cm}}^{-1}$, CYT.c
973	$═\mathrm{C}─\mathrm{H}$ out of plane deformation $\mathrm{C}─\mathrm{C}$ Asym. Str.	deoxygenated of cells porphyrin macrocycle
1004	Symmetric CC aromatic ring breathing	Phenylalanine, Collagen IV, I
1088	CC stretch, CC skeletal stretch trans, ${\mathrm{PO}}_2$ symmetric	Protein, phospholipid, glycogen Collagen IV, I
1128	$\mathrm{C}─\mathrm{C}$ stretching, trans	Lipids
1156	$\mathrm{C}═\mathrm{C}$ stretch	$\beta$-carotene
1173	$\mathrm{C}─\mathrm{H}$ in-plane bending	Tyrosine, hemoglobin, Flavin
1214 >(1200–1300)	Amide III	Homo polypeptide
1301	Amide III, $\delta$ ($\mathrm{N}─\mathrm{H}$)-30%, $\alpha$-helix, $\mathrm{\nu }$ ($\mathrm{C}─\mathrm{N}$)-40% & $\delta ({\mathrm{CH}}_3)$	$\delta$ and $\mathrm{\nu }$ Coupled in-phase, Collagen IV, I
1338	${\mathrm{CH}}_2$ Deformation	Protein, A and G of DNA/RNA
1358	${\mathrm{CH}}_3─(\mathrm{C}═\mathrm{O})$,	Trp., mitochondria, CYTc
1378	${\mathrm{CH}}_3$ in-phase deformation	T, A, G of DNA
1428–1471	$\delta$ (CN) bending, $\delta {(\mathrm{CH})}_3$ out-of-phase deformation	Lipid, protein
1527 (1500–1600)	Amide II, Shift to 1548, ($\mathrm{C}═\mathrm{C}$) stretch	parallel $\beta$-sheet, protein, tryp., carotenoid ($1532{\mathrm{cm}}^{-1}$ in cancer)
1548	Amide II, in plane $\delta$ ($\mathrm{N}─\mathrm{H}$) bending: 60%; $\nu$ ($\mathrm{C}─\mathrm{N}$):40%;	Trp, cytochrome c, $\delta$ and $\mathrm{\nu }$ coupled out-of-phase, NADH
1587	$\mathrm{C}─\mathrm{C}$ stretching, $\mathrm{C}─\mathrm{H}$ bending	Trp, mitochondria, NADH
1605	CO stretching, $\mathrm{C}═\mathrm{C}$ bending	Phe., tyr.
1639	Amide I in $\alpha$-helix	protein
1667	Amide I, $\beta$-sheet, $\nu$ ($\mathrm{C}═\mathrm{O}$) 80%	Salt environment effect, Unordered or random structure, Collagen IV, I
1732	$\mathrm{\nu }$ ($\mathrm{C}═\mathrm{C}$)	Lipids, phospholipids
2727	$1378{\mathrm{cm}}^{-1}$ bend overtone
2850	$\nu ({\mathrm{CH}}_2)$	Poly methylene chain, F
2891	$\nu$ (${\mathrm{CH}}_2$, FR)	Poly methylene chain
2934	$\nu$ (${\mathrm{CH}}_3$, FR)	P.F.
3060	${\mathrm{CH}}_3─(\mathrm{C}═\mathrm{O})$
3104	$\nu (\mathrm{O}─\mathrm{H})$ water band
3156	$\nu (\mathrm{O}─\mathrm{H})$ water band
3288	$\mathrm{O}─\mathrm{H}$, Liquid water
3444	$\mathrm{O}─\mathrm{H}$, Liquid water

^aRefs: [20, 21, 24, 30, 31, 33, 34, 35]; $\nu$: stretch; FR: Fermi resonance; $\delta$: bending; sym.: symmetric, trp.: tryptophan, CYTc: cytochrome c; P: protein; F: fat.