On the percolation of alginate/calcium systems at low concentrations
Journal article, 2016

The sol-to-gel transition of an alginate rich in β-d-mannuronic acid residues and at a concentration of 0.1% w/v in 15 mM NaCl in the presence of calcium ions of 0 to 3.5 mM was studied with dynamic light scattering. The dynamics of the different systems added further insight into the alginate gel forming mechanisms. Below a Ca2+ concentration of 0.7 mM, the build-up of small aggregates could be verified. Moreover, at a critical concentration, close to 0.9 mM Ca2+, a percolated, non-ergodic network started to form from some of these aggregates, with smaller aggregates still diffusing in the network. The system displayed strong non-ergodicy at high Ca2+ concentrations with a non-ergodicity parameter that appeared to form discontinuously from near zero to a clearly non-zero value at the critical Ca2+ concentration.

Alginate

gel

dynamic light scattering

structure dynamics

Author

Adele Khavari

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

SuMo Biomaterials

Jan-Erik Löfroth

Chalmers, Chemistry and Chemical Engineering, Applied Chemistry, Applied Surface Chemistry

Johan Bergenholtz

University of Gothenburg

Magnus Nydén

University College London (UCL)

Carbohydrate Polymers

0144-8617 (ISSN)

Vol. 137 480-487

Subject Categories

Polymer Chemistry

Physical Chemistry

DOI

10.1016/j.carbpol.2015.11.019