Table 1.
Band assignments of mid-IR spectra common to biological samples.
| Band maxima (cm−1) | Band assignments |
|---|---|
| ~2962 | C–H stretching peak of lipids and proteins |
| ~2923 | C–H asymmetrical stretching of lipid groups and protein |
| ~2850 | C–H symmetrical stretching of lipid groups |
| ~1743 | C=O stretching of lipid esters |
| ~1685 | β-turn protein secondary structure |
| ~1654 | α-helical protein secondary structure |
| ~1635 | β-pleated sheet protein secondary structure |
| ~1554 | Overall protein absorbance |
| ~1458 | Methyl and methylene groups from lipids and protein |
| ~1396 | COO− stretching vibrations of amino acid side chains |
| ~1238 | P=O asymmetrical stretching of PO2 phosphodiester groups from phosphorylated molecules |
| ~1080 | P=O symmetrical stretching of PO2 phosphodiester groups from phosphorylated molecules, and glycogen |
| ~1153 | C–O vibrations from glycogen and other carbohydrates |
| ~1050 | C–O vibrations from glycogen and other carbohydrates |
| ~1022 | C–O vibrations from glycogen and other carbohydrates |
| ~995 | C–O stretch from RNA ribose chain and other carbohydrates |
| ~950 | C–C vibrations from nucleic acids |