Formalin Fixation as Tissue Preprocessing for Multimodal Optical Spectroscopy Using the Example of Human Brain Tumour Cross Sections

Table 1

Spectral band assignments for brain tumors for the FTIR models.

Band position (cm^−1)	Assignments	Remarks	References
2960–2850	ν (CH), ν (CH2), ν (CH3)	Fatty acids	[32, 67]
∼1750	Ν (C = O)	Lipids	[32, 68, 69]
∼1655, ∼1582, ∼1547	ν (C = O), ν (C–N)	Amide I and amide II of proteins and peptides	[32, 67–71]
∼1415	ν (–COO)	Amino acid side chain	[71]
1455–1460	ν (CH3)	Amino acid side chain	[32, 67, 71]
∼1465, ∼1385	ν (CH2), ν (CH3)	Cholesterol, phospholipids	[32]
1234, 1063	ν (PO2)	Phosphate, phosphodiesters of RNA and DNA	[32, 67, 68, 71]
∼1165	ν (C–O)	RNA and/or carbohydrates	[71]
∼1200, ∼1170	ν (C–O)	Proteins	[32]
∼1200–900	ν (C–O), ν (C–C), ν (C–O–H), ν (C–O–C)	Carbohydrates	[67, 68]
1040–1110	ν (C–O)	RNA and DNA	[71]