Articolo in rivista, 2003, , 10.1016/S0301-4622(02)00341-1
Mangione M.R. 1,2, Giacomazza D. 1, Bulone D. 1, Martorana V. 1, San Biagio P.L. 1
1: CNR; 2: Uni Palermo
We have studied, by optical rotation dispersion, light scattering and rheology, the kappa-Carrageenan system to elucidate the processes involved in gel formation (on decreasing the temperature) and gel melting (on increasing the temperature). Our results show that, on decreasing the temperature, a conformational transition from coils to double helices first occurs, followed by aggregation of the double helices into domains and gel formation at appropriate polymer concentration. Structural details of this sequence are better revealed by re-heating the system. Melting appears as a two-step process characterized by first a conformational change of helices involved in junction zones between aggregates, followed by the conformational transition of the helices inside the aggregates. These helices can regain the coil conformation only when the aggregates melt at higher temperature, in full agreement with the old 'domain' model. The full description of the sol-gel mechanism of this system can be useful in the search for new methods to control the gel texture, a relevant property for many industrial applications.
Biophysical chemistry (Print) 104 , pp. 95–105
Self-assembly, Gelation, Carrageenan
Martorana Vincenzo, Bulone Donatella, San Biagio Pier Luigi, Mangione Maria Rosalia, Giacomazza Daniela
ID: 9412
Year: 2003
Type: Articolo in rivista
Creation: 2009-06-16 00:00:00.000
Last update: 2018-09-27 15:02:40.000
CNR institutes
External IDs
CNR OAI-PMH: oai:it.cnr:prodotti:9412
DOI: 10.1016/S0301-4622(02)00341-1
ISI Web of Science (WOS): 000184020500010