Aqueous foams are extremely complex systems with a cellular internal structure, consisting of polydisperse gas bubbles separated by thin liquid films. The foam evolution and its transient stability are functions of drainage and rupture of liquid films between air bubbles.
Our aim was to develop a new technology of generating of bio-inspired, easy degradable, biopolymer based aqueous foams for biomedical application. Thus, the specific objective of this work was to find correlations between surface activity and foaming properties of biopolymers solutions and biopolymers/surfactant mixtures. The foams of the pure biopolymers (proteins like BSA, casein and polysaccharides i.e. methyl cellulose, alginic acid) and solutions of their mixtures with anionic surfactant (lauric arginate LAE) were analyzed.
Foam stability was determined by monitoring the liquid drainage out of the foam volume with two complementary techniques: i) in a classical foam column, where the decreasing of the foam height and variations of the bottom liquid level were measured and ii) in a rotational Hele-Shaw cell (2D foam) for the evolution of the local liquid fraction on various levels of foam. Dynamic surface tension measurements were chosen to investigate the adsorption state in the interface layer under dynamic conditions. Additionally, the rising bubble method was used to determine the concentration of biopolymer and its mixture with lauric arginate that allows a complete immobilization of the bubble surface just after detachment from the capillary orifice.
Acknowledgements: Financial support from Polish National Scientific Centre (grant no. 2011/01/ST8/03717) is gratefully acknowledged. Part of this work has been also supported by COST actions MP1106 and CM1101. The authors want also thanks the Vedeqsa Inc., which kindly provided LAE (Mirenat).
ncwarszy@cyf-kr.edu.pl
