Bibliographic Details
| Summary: | A set of carrageenans produced in the potassium form and with chemical structures varying from pure iota-carrageenans to nearly pure kappa-carrageenans is submitted to ultrasonication to reduce their molecular masses Mw while maintaining a constant chemical structure and a polydispersity index around 2. The kinetics of ultrasound-induced chain scission are found to be slower for polysaccharides richer in kappa-carrageenan disaccharide units. From the elasticity of samples directly gelled in a rheometer at 1 w/v% in 0.1 M potassium chloride, a critical molecular mass Mc is identified as the mass below which no gel can be formed. Mc is found to be smaller for kappa- and kappa-2-carrageenans of the order of 0.13-0.21 MDa. The presence of more sulphated disaccharide units significantly increases Mc up to 0.28 MDa for iota-carrageenan and 0.57 MDa for a highly sulphated hybrid carrageenan. For the set of Mw and carrageenans tested, no plateau in the Mw dependence of the gels' elasticities is found. |
|---|
| Main Authors: | Gonçalves, Maria Gabriela Afonso |
|---|
| Other Authors: | Faria, Bruno Miguel Silva; Moraes, Izabel Cristina Freitas; Hilliou, L. |
|---|
| Subject: | Carrageenan Hydrogel Molecular mass Shear storage modulus |
|---|
| Year: | 2025 |
|---|
| Country: | Portugal |
|---|
| Document type: | article |
|---|
| Access type: | open access |
|---|
| Associated institution: | Universidade do Minho |
|---|
| Language: | English |
|---|
| Origin: | RepositóriUM - Universidade do Minho |
|---|