Tentative infrared bands assignment (cm–1)
| Sodium alginate | κ-carrageenan | Assignment |
|---|---|---|
| 3,443 | 3,600–3,100 | (OH) |
| 3,100–2,800 | (CH) | |
| 2,970 | ν(OH) | |
| 1,642 | δ(OH) | |
| 1,610 | νasymmetric (COO–) | |
| 1,417 | νsymmetric (COO–) | |
| 1,238 | ν(S=O) | |
| 1,258 | ν(C–O) | |
| 1,165 | ν(C–O), ν(C–C) and δ (C–C–C) | |
| 912 | ν(C–O–C) glycosidic bond | |
| 848/704 | δ(C–O–S) |